U.S. patent application number 15/564492 was filed with the patent office on 2018-03-15 for usage-side air-conditioning apparatus and air-conditioning apparatus provided with same.
This patent application is currently assigned to DAIKIN INDUSTRIES, LTD.. The applicant listed for this patent is DAIKIN INDUSTRIES, LTD.. Invention is credited to Shingo ITOU, Kouji MIWA, Ryuuzaburou YAJIMA.
Application Number | 20180073762 15/564492 |
Document ID | / |
Family ID | 57358340 |
Filed Date | 2018-03-15 |
United States Patent
Application |
20180073762 |
Kind Code |
A1 |
YAJIMA; Ryuuzaburou ; et
al. |
March 15, 2018 |
USAGE-SIDE AIR-CONDITIONING APPARATUS AND AIR-CONDITIONING
APPARATUS PROVIDED WITH SAME
Abstract
A usage-side air-conditioning apparatus has: a casing; a
usage-side heat exchanger to cool or heat air inside the casing
through the use of a refrigerant supplied from a heat-source-side
air-conditioning apparatus; an air supply/exhaust mechanism to take
room air and/or outdoor air in from an air-conditioned space or
outside of the air-conditioned space, supply the air as supply air
to the air-conditioned space, and exhaust the air as exhaust air
out of the air-conditioned space; and a refrigerant leakage
detection device to detect the refrigerant. When the refrigerant
leakage detection device has detected the refrigerant, a
refrigerant exhaust operation is performed by the air
supply/exhaust mechanism to exhaust the refrigerant out of the
air-conditioned space along with the air inside the casing.
Inventors: |
YAJIMA; Ryuuzaburou;
(Osaka-shi, JP) ; ITOU; Shingo; (Osaka-shi,
JP) ; MIWA; Kouji; (Osaka-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DAIKIN INDUSTRIES, LTD. |
Osaka-shi, Osaka |
|
JP |
|
|
Assignee: |
DAIKIN INDUSTRIES, LTD.
Osaka-shi, Osaka
JP
|
Family ID: |
57358340 |
Appl. No.: |
15/564492 |
Filed: |
April 6, 2016 |
PCT Filed: |
April 6, 2016 |
PCT NO: |
PCT/JP2016/061213 |
371 Date: |
October 5, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F25B 2400/12 20130101;
F24F 11/89 20180101; F24F 11/65 20180101; F24F 11/0001 20130101;
F24F 3/147 20130101; F24F 11/30 20180101; F24F 2110/50 20180101;
F25B 2313/0293 20130101; F25B 13/00 20130101; F24F 7/08 20130101;
F25B 2313/0233 20130101; F24F 11/36 20180101 |
International
Class: |
F24F 11/02 20060101
F24F011/02; F24F 7/08 20060101 F24F007/08; F24F 11/00 20060101
F24F011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 6, 2015 |
JP |
2015-077487 |
Apr 7, 2015 |
JP |
2015-078725 |
Claims
1. A usage-side air-conditioning apparatus comprising: a casing; a
usage-side heat exchanger, being provided inside the casing, to
cool or heat air inside the casing through the use of a refrigerant
supplied from a heat-source-side air-conditioning apparatus; an air
supply/exhaust mechanism to take room air into the casing from an
air-conditioned space, take outdoor air into the casing from
outside the air-conditioned space, supply the air inside the casing
as supply air to the air-conditioned space, and exhaust the air
inside the casing as exhaust air out of the air-conditioned space;
and a refrigerant leakage detection device to detect the
refrigerant; wherein a refrigerant exhaust operation is performed
by the air supply/exhaust mechanism to exhaust the refrigerant out
of the air-conditioned space along with the air inside the casing
when the refrigerant leakage detection device has detected the
refrigerant.
2. The usage-side air-conditioning apparatus according to claim 1,
wherein a total heat exchanger to perform heat exchange between the
outdoor air and the room air is provided inside the casing; the air
supply/exhaust mechanism has a first air supply blower provided so
as to be able to take outdoor air in from outside the
air-conditioned space and supply the supply air to the
air-conditioned space, and a first air exhaust blower provided so
as to be able to take room air in from the air-conditioned space
and exhaust the exhaust air out of the air-conditioned space; and
the refrigerant exhaust operation is performed by operating the
first air exhaust blower.
3. The usage-side air-conditioning apparatus according to claim 1,
wherein the air supply/exhaust mechanism has an air supply/exhaust
blower provided to be capable of switching between an air supply
state of taking the room air in from the air-conditioned space,
taking the outdoor air in from outside the air-conditioned space,
and supplying the supply air to the air-conditioned space, and an
air exhaust state of exhausting the exhaust air out of the
air-conditioned space; and the refrigerant exhaust operation is
performed by operating the air supply/exhaust blower in the air
exhaust state.
4. The usage-side air-conditioning apparatus according to claim 1,
wherein the air supply/exhaust mechanism has a second air supply
blower provided so as to be capable of taking the room air in from
the air-conditioned space, taking the outdoor air in from outside
the air-conditioned space, and supplying the supply air to the
air-conditioned space, and a second air exhaust blower provided so
as to be capable of exhausting the exhaust air out of the
air-conditioned space; and the refrigerant exhaust operation is
performed by operating the second air exhaust blower.
5. The usage-side air-conditioning apparatus according to claim 1,
wherein the air supply/exhaust mechanism has a third air supply
blower provided so as to be capable of taking the outdoor air in
from outside the air-conditioned space and supplying the supply air
to the air-conditioned space, and a third air exhaust blower
provided so as to be capable of taking the room air in from the
air-conditioned space, returning some of the room air to the
outdoor air taken in by the third air supply blower, and exhausting
a remnant of the room air as the exhaust air out of the
air-conditioned space; and the refrigerant exhaust operation is
performed by operating the third air exhaust blower.
6. The usage-side air-conditioning apparatus according to claim 1,
wherein the usage-side heat exchanger is connected to the
heat-source-side air-conditioning apparatus via a refrigerant
interconnection pipe; and a joint to connect the usage-side heat
exchanger to the refrigerant interconnection pipe is provided
inside the casing.
7. The usage-side air-conditioning apparatus according to claim 1,
wherein the usage-side heat exchanger is connected to the
heat-source-side air-conditioning apparatus via a refrigerant
interconnection pipe; a joint to connect the usage-side heat
exchanger to the refrigerant interconnection pipe is provided
outside the casing; the air supply/exhaust mechanism has an
inside-outside communication mechanism capable of switching between
an inside-outside communication state of allowing communication
between the casing interior and a usage-side installation space in
which the casing is provided, and an inside-outside
non-communication state of not allowing communication between the
casing interior and the usage-side installation space; and the
refrigerant exhaust operation is performed by putting the
inside-outside communication mechanism in the inside-outside
communication state.
8. The usage-side air-conditioning apparatus according to claim 1,
wherein the refrigerant is denser than air; and the refrigerant
leakage detection device is provided to a lower part of the
casing.
9. The usage-side air-conditioning apparatus according to claim 1,
wherein the refrigerant is less dense than air; and the refrigerant
leakage detection device is provided to an upper part of the
casing.
10. The usage-side air-conditioning apparatus according to claim 1,
wherein the refrigerant is slightly flammable or flammable.
11. The usage-side air-conditioning apparatus according claim 1,
wherein the refrigerant is toxic.
12. The usage-side air-conditioning apparatus according to claim 1,
wherein the refrigerant is not slightly flammable, flammable, or
toxic.
13. An air-conditioning apparatus configured by connecting a
heat-source-side air-conditioning apparatus to supply refrigerant,
and a plurality of the usage-side air-conditioning apparatuses
according to claim 1.
14. An air conditioning apparatus according to claim 13, wherein a
total heat exchanger to perform heat exchange between the outdoor
air and the room air is provided inside the casing; the air
supply/exhaust mechanism has a first air supply blower provided so
as to be able to take outdoor air in from outside the
air-conditioned space and supply the supply air to the
air-conditioned space, and a first air exhaust blower provided so
as to be able to take room air in from the air-conditioned space
and exhaust the exhaust air out of the air-conditioned space; and
the refrigerant exhaust operation is performed by operating the
first air exhaust blower.
15. An air conditioning apparatus according to claim 13, wherein
the air supply/exhaust mechanism has an air supply/exhaust blower
provided to be capable of switching between an air supply state of
taking the room air in from the air-conditioned space, taking the
outdoor air in from outside the air-conditioned space, and
supplying the supply air to the air-conditioned space, and an air
exhaust state of exhausting the exhaust air out of the
air-conditioned space; and the refrigerant exhaust operation is
performed by operating the air supply/exhaust blower in the air
exhaust state.
16. An air conditioning apparatus according to claim 13, wherein
the air supply/exhaust mechanism has a second air supply blower
provided so as to be capable of taking the room air in from the
air-conditioned space, taking the outdoor air in from outside the
air-conditioned space, and supplying the supply air to the
air-conditioned space, and a second air exhaust blower provided so
as to be capable of exhausting the exhaust air out of the
air-conditioned space; and the refrigerant exhaust operation is
performed by operating the second air exhaust blower.
17. An air conditioning apparatus according to claim 13, wherein
the air supply/exhaust mechanism has a third air supply blower
provided so as to be capable of taking the outdoor air in from
outside the air-conditioned space and supplying the supply air to
the air-conditioned space, and a third air exhaust blower provided
so as to be capable of taking the room air in from the
air-conditioned space, returning some of the room air to the
outdoor air taken in by the third air supply blower, and exhausting
a remnant of the room air as the exhaust air out of the
air-conditioned space; and the refrigerant exhaust operation is
performed by operating the third air exhaust blower.
18. An air conditioning apparatus according to claim 13, wherein
the usage-side heat exchanger is connected to the heat-source-side
air-conditioning apparatus via a refrigerant interconnection pipe;
and a joint to connect the usage-side heat exchanger to the
refrigerant interconnection pipe is provided inside the casing.
19. An air conditioning apparatus according to claim 13, wherein
the usage-side heat exchanger is connected to the heat-source-side
air-conditioning apparatus via a refrigerant interconnection pipe;
a joint to connect the usage-side heat exchanger to the refrigerant
interconnection pipe is provided outside the casing; the air
supply/exhaust mechanism has an inside-outside communication
mechanism capable of switching between an inside-outside
communication state of allowing communication between the casing
interior and a usage-side installation space in which the casing is
provided, and an inside-outside non-communication state of not
allowing communication between the casing interior and the
usage-side installation space; and the refrigerant exhaust
operation is performed by putting the inside-outside communication
mechanism in the inside-outside communication state.
20. An air conditioning apparatus according to claim 13, wherein
the refrigerant is denser than air; and the refrigerant leakage
detection device is provided to a lower part of the casing.
Description
TECHNICAL FIELD
[0001] The present invention relates to a usage-side
air-conditioning apparatus, and particularly relates to: a
usage-side air-conditioning apparatus having a usage-side heat
exchanger to cool or heat air inside a casing by means of a
refrigerant supplied from a heat-source-side air-conditioning
apparatus, and an air supply/exhaust mechanism to take air into the
casing from an air-conditioned space or outside an air-conditioned
space and/or to supply the air inside the casing to the
air-conditioned space or to the outside of the air-conditioned
space; and an air-conditioning apparatus provided with such a
usage-side air-conditioning apparatus.
BACKGROUND ART
[0002] In the past there have been ventilating air conditioners
(usage-side air-conditioning apparatuses) that have an evaporator
and/or condenser (usage-side heat exchangers) to cool or heat air
inside a casing by means of a refrigerant supplied from an outdoor
machine (a heat-source-side air-conditioning apparatus), and an air
supply fan and/or air exhaust fan (air supply/exhaust mechanism) to
take air into the casing from an air-conditioned space or outside
an air-conditioned space and/or to supply the air inside the casing
to the air-conditioned space or to the outside of the
air-conditioned space, as is disclosed in Patent Literature 1
(Japanese Laid-open Patent Publication No. 2000-220877).
SUMMARY OF THE INVENTION
[0003] In such a usage-side air-conditioning apparatus having a
ventilating air-condition function to ventilate and air-condition
the interior of a room, when refrigerant leaks, there is a risk
that the leaked refrigerant will be supplied to the air-conditioned
space, and an oxygen deficiency accident, an ignition accident
(when the refrigerant is slightly flammable or flammable), or a
poisoning accident (when the refrigerant is toxic) will occur.
[0004] An object of the present invention is to ensure that when
refrigerant leaks in a usage-side air-conditioning apparatus having
a ventilating air-condition function and an air-conditioning
apparatus provided with the same, the leaked refrigerant is quickly
exhausted and not supplied to an air-conditioned space.
[0005] A usage-side air-conditioning apparatus according to a first
aspect of the present invention comprises a casing, a usage-side
heat exchanger, an air supply/exhaust mechanism, and a refrigerant
leakage detection device. The usage-side heat exchanger, which is
provided inside the casing, cools or heats air inside the casing
through the use of a refrigerant supplied from a heat-source-side
air-conditioning apparatus. The air supply/exhaust mechanism takes
room air into the casing from an air-conditioned space, takes
outdoor air into the casing from outside the air-conditioned space,
supplies the air inside the casing as supply air to the
air-conditioned space, and exhausts the air inside the casing as
exhaust air out of the air-conditioned space. The refrigerant
leakage detection device detects the refrigerant. In this aspect,
when the refrigerant leakage detection device has detected the
refrigerant, a refrigerant exhaust operation is performed by the
air supply/exhaust mechanism to exhaust the refrigerant out of the
air-conditioned space along with the air inside the casing.
[0006] In this aspect, when the refrigerant has leaked, the leaked
refrigerant can be quickly exhausted and prevented from being
supplied to the air-conditioned space, using the air supply/exhaust
mechanism.
[0007] A usage-side air-conditioning apparatus according to a
second aspect is the usage-side air-conditioning apparatus
according to the first aspect, wherein a total heat exchanger to
perform heat exchange between the outdoor air and the room air is
provided inside the casing, and the air supply/exhaust mechanism
has a first air supply blower provided so as to be able to take
outdoor air in from outside the air-conditioned space and supply
the supply air to the air-conditioned space, and a first air
exhaust blower provided so as to be able to take room air in from
the air-conditioned space and exhaust the exhaust air out of the
air-conditioned space. In this aspect, the refrigerant exhaust
operation is performed by operating the first air exhaust
blower.
[0008] In this aspect, when the refrigerant has leaked, the leaked
refrigerant can be quickly exhausted and prevented from being
supplied to the air-conditioned space, by operating the first air
exhaust blower configuring the air supply/exhaust mechanism.
[0009] A usage-side air-conditioning apparatus according to a third
aspect is the usage-side air-conditioning apparatus according to
the first aspect, wherein the air supply/exhaust mechanism has an
air supply/exhaust blower provided to be capable of switching
between an air supply state of taking the room air in from the
air-conditioned space, taking the outdoor air in from outside the
air-conditioned space, and supplying the supply air to the
air-conditioned space, and an air exhaust state of exhausting the
exhaust air out of the air-conditioned space. In this aspect, the
refrigerant exhaust operation is performed by operating the air
supply/exhaust blower in the air exhaust state.
[0010] In this aspect, when the refrigerant has leaked, the leaked
refrigerant can be quickly exhausted and prevented from being
supplied to the air-conditioned space, by operating the air
supply/exhaust blower configuring the air supply/exhaust mechanism
in the air exhaust state.
[0011] A usage-side air-conditioning apparatus according to a
fourth aspect is the usage-side air-conditioning apparatus
according to the first aspect, wherein the air supply/exhaust
mechanism has a second air supply blower provided so as to be
capable of taking the room air in from the air-conditioned space,
taking the outdoor air in from outside the air-conditioned space,
and supplying the supply air to the air-conditioned space, and a
second air exhaust blower provided so as to be capable of
exhausting the exhaust air out of the air-conditioned space. In
this aspect, the refrigerant exhaust operation is performed by
operating the second air exhaust blower.
[0012] In this aspect, when the refrigerant has leaked, the leaked
refrigerant can be quickly exhausted and prevented from being
supplied to the air-conditioned space, by operating the second air
exhaust blower configuring the air supply/exhaust mechanism.
[0013] A usage-side air-conditioning apparatus according to a fifth
aspect is the usage-side air-conditioning apparatus according to
the first aspect, wherein the air supply/exhaust mechanism has a
third air supply blower provided so as to be capable of taking the
outdoor air in from outside the air-conditioned space and supplying
the supply air to the air-conditioned space, and a third air
exhaust blower provided so as to be capable of taking the room air
in from the air-conditioned space, returning some of the room air
to the outdoor air taken in by the third air supply blower, and
exhausting the remnant of the room air as the exhaust air out of
the air-conditioned space. In this aspect, the refrigerant exhaust
operation is performed by operating the third air exhaust
blower.
[0014] In this aspect, when the refrigerant has leaked, the leaked
refrigerant can be quickly exhausted and prevented from being
supplied to the air-conditioned space, by operating the third air
exhaust blower configuring the air supply/exhaust mechanism.
[0015] A usage-side air-conditioning apparatus according to a sixth
aspect is the usage-side air-conditioning apparatus according to
any of the first through fifth aspects, wherein the usage-side heat
exchanger is connected to the heat-source-side air-conditioning
apparatus via a refrigerant interconnection pipe. In this aspect, a
joint to connect the usage-side heat exchanger to the refrigerant
interconnection pipe is provided inside the casing.
[0016] In this aspect, when the refrigerant has leaked from the
joint to connect the usage-side heat exchanger to the refrigerant
interconnection pipe, the refrigerant leaks into the casing.
Therefore, when the refrigerant has leaked, the refrigerant can be
quickly detected, and the leaked refrigerant can be quickly
exhausted.
[0017] A usage-side air-conditioning apparatus according to a
seventh aspect is the usage-side air-conditioning apparatus
according to any of the first through fifth aspects, wherein the
usage-side heat exchanger is connected to the heat-source-side
air-conditioning apparatus via the refrigerant interconnection
pipe, and a joint to connect the usage-side heat exchanger to the
refrigerant interconnection pipe is provided outside the casing. In
this aspect, the air supply/exhaust mechanism has an inside-outside
communication mechanism capable of switching between an
inside-outside communication state of allowing communication
between the casing interior and a usage-side installation space in
which the casing is provided, and an inside-outside
non-communication state of not allowing communication between the
casing interior and the usage-side installation space, and the
refrigerant exhaust operation is performed by putting the
inside-outside communication mechanism in the inside-outside
communication state.
[0018] In this aspect, when the refrigerant has leaked from the
joint to connect the usage-side heat exchanger to the refrigerant
interconnection pipe, the refrigerant leaks into the usage-side
installation space. However, in this aspect, the usage-side
installation space and the casing interior can be allowed to
communicate by the inside-outside communication mechanism.
Therefore, in this aspect, when refrigerant has leaked, the
refrigerant leaked into the usage-side installation space can be
quickly exhausted while being guided into the casing, and prevented
from being supplied to the air-conditioned space, using the air
supply/exhaust mechanism including the inside-outside communication
mechanism.
[0019] A usage-side air-conditioning apparatus according to an
eighth aspect is the usage-side air-conditioning apparatus
according to any of the first through seventh aspects, wherein the
refrigerant is denser than air; and the refrigerant leakage
detection device is provided to a lower part of the casing.
[0020] In this aspect, the refrigerant can be quickly detected
using the tendency of the refrigerant denser than air to accumulate
downward.
[0021] A usage-side air-conditioning apparatus according to a ninth
aspect is the usage-side air-conditioning apparatus according to
any of the first through seventh aspects, wherein the refrigerant
is less dense than air; and the refrigerant leakage detection
device is provided to an upper part of the casing.
[0022] In this aspect, the refrigerant can be quickly detected
using the tendency of the refrigerant less dense than air to
accumulate upward.
[0023] A usage-side air-conditioning apparatus according to a tenth
aspect is the usage-side air-conditioning apparatus according to
any of the first through ninth aspects, wherein the refrigerant is
slightly flammable or flammable.
[0024] In this aspect, the occurrence of ignition accidents in the
air-conditioned space can be suppressed.
[0025] A usage-side air-conditioning apparatus according to an
eleventh aspect is the usage-side air-conditioning apparatus
according to any of the first through ninth aspects, wherein the
refrigerant is toxic.
[0026] In this aspect, the occurrence of poisoning accidents in the
air-conditioned space can be suppressed.
[0027] A usage-side air-conditioning apparatus according to a
twelfth aspect is the usage-side air-conditioning apparatus
according to any of the first through ninth aspects, wherein the
refrigerant is not slightly flammable, flammable, or toxic.
[0028] In this aspect, the occurrence of oxygen deficiency
accidents in the air-conditioned space can be suppressed.
[0029] An air-conditioning apparatus according to a thirteenth
aspect is configured by connecting a heat-source-side
air-conditioning apparatus supplying refrigerant to a plurality of
the usage-side air-conditioning apparatuses according to any of the
first through twelfth aspects.
[0030] In this aspect, when the refrigerant has leaked in any of
the plurality of usage-side air-conditioning apparatuses, the
leaked refrigerant can be quickly exhausted using the air
supply/exhaust mechanism of the usage-side air-conditioning
apparatus in which the refrigerant has leaked, and the refrigerant
can be prevented from being supplied to the air-conditioned space
that is air-conditioned by the usage-side air-conditioning
apparatus in which the refrigerant has leaked.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 is an overall configuration diagram of usage-side
air-conditioning apparatuses according to a first embodiment of the
present invention, and an air-conditioning apparatus provided with
the same (the flow of air during normal operation and the like are
also illustrated);
[0032] FIG. 2 is a control block diagram of the air-conditioning
apparatus in the first embodiment;
[0033] FIG. 3 is a diagram showing air flow during a refrigerant
exhaust operation and the like in the first embodiment;
[0034] FIG. 4 is an overall configuration diagram of the usage-side
air-conditioning apparatuses according to a modification of the
first embodiment and an air-conditioning apparatus provided with
the same (the flow of air during normal operation and the like are
also illustrated);
[0035] FIG. 5 is a diagram showing air flow during a refrigerant
exhaust operation and the like in a modification of the first
embodiment;
[0036] FIG. 6 is an overall configuration diagram of usage-side
air-conditioning apparatuses according to a second embodiment of
the present invention, and an air-conditioning apparatus provided
with the same (the flow of air during normal operation and the like
are also illustrated);
[0037] FIG. 7 is a control block diagram of the air-conditioning
apparatus in the second embodiment;
[0038] FIG. 8 is a diagram showing air flow during a refrigerant
exhaust operation and the like in the second embodiment;
[0039] FIG. 9 is an overall configuration diagram of usage-side
air-conditioning apparatuses according to a third embodiment of the
present invention, and an air-conditioning apparatus provided with
the same (the flow of air during normal operation and the like are
also illustrated);
[0040] FIG. 10 is a control block diagram of the air-conditioning
apparatus in the third embodiment;
[0041] FIG. 11 is a diagram showing air flow during a refrigerant
exhaust operation and the like in the third embodiment;
[0042] FIG. 12 is an overall configuration diagram of usage-side
air-conditioning apparatuses according to a fourth embodiment of
the present invention, and an air-conditioning apparatus provided
with the same (the flow of air during normal operation and the like
are also illustrated);
[0043] FIG. 13 is a control block diagram of the air-conditioning
apparatus in the fourth embodiment; and
[0044] FIG. 14 is a diagram showing air flow during a refrigerant
exhaust operation and the like in the fourth embodiment.
DESCRIPTION OF EMBODIMENTS
[0045] An embodiment of a usage-side air-conditioning apparatus
according to the present invention and an air-conditioning
apparatus provided with the same is described below with reference
to the drawings. The specific configuration of an embodiment of the
air-conditioning apparatus according to the present invention is
not limited to the following embodiments or modifications thereof;
the configuration can be changed within a range that does not
deviate from the scope of the invention.
First Embodiment
[0046] (1) Configuration
[0047] FIG. 1 is an overall configuration diagram of usage-side
air-conditioning apparatuses 3a, 3b according to a first embodiment
of the present invention, and an air-conditioning apparatus 1
provided with the same. FIG. 2 is a control block diagram of the
air-conditioning apparatus 1 in the first embodiment.
[0048] <Overall>
[0049] The air-conditioning apparatus 1, which is an
air-conditioning ventilation system having a ventilating
air-condition function for ventilating and air-conditioning the
interior of a room, mainly has a heat-source-side air-conditioning
apparatus 2, and a plurality (two in this embodiment) of usage-side
air-conditioning apparatuses 3a, 3b.
[0050] The air-conditioning apparatus 1 has a refrigerant circuit
10 through which refrigerant circulates. The refrigerant circuit 10
is configured by connecting the heat-source-side air-conditioning
apparatus 2 to the usage-side air-conditioning apparatuses 3a, 3b.
In this embodiment, the heat-source-side air-conditioning apparatus
2 is installed in a location such as on the roof of a building, and
the usage-side air-conditioning apparatuses 3a, 3b are installed in
usage-side installation spaces (in this embodiment, usage-side
installation spaces S3, S4), such as a machine room of the building
or a space above the ceiling, in correspondence with
air-conditioned spaces (in this embodiment, air-conditioned spaces
S1, S2) that are ventilated and air-conditioned. The
heat-source-side air-conditioning apparatus 2 and the usage-side
air-conditioning apparatuses 3a, 3b are connected via refrigerant
interconnection pipes 11, 12, thereby configuring the refrigerant
circuit 10. The refrigerant sealed within the refrigerant circuit
10 is a slightly flammable refrigerant such as R32, a flammable
refrigerant such as propane, or a toxic refrigerant such as
ammonia.
[0051] The air-conditioning apparatus 1 has a plurality of air
ducts. In this embodiment, the air-conditioning apparatus 1 has an
intake duct 5 for taking outdoor air (OA) into the usage-side
air-conditioning apparatuses 3a, 3b from outside the
air-conditioned spaces S1, S2, air supply ducts 6a, 6b for
supplying supply air (SA) from the usage-side air-conditioning
apparatuses 3a, 3b to the air-conditioned spaces S1, S2, outtake
ducts 7a, 7b for taking room air (RA) from the air-conditioned
spaces S1, S2 into the corresponding usage-side air-conditioning
apparatuses 3a, 3b, and an air exhaust duct 8 for exhausting
exhaust air (EA) out of the air-conditioned spaces S1, S2 from the
usage-side air-conditioning apparatuses 3a, 3b. Air can thereby be
exchanged between the air-conditioned spaces S1, S2 and/or the
outsides of the air-conditioned spaces S1, S2 and the usage-side
air-conditioning apparatuses 3a, 3b. The intake duct 5 has intake
branch ducts 5a, 5b that branch corresponding to the usage-side
air-conditioning apparatuses 3a, 3b, and the air exhaust duct 8 has
air exhaust branch ducts 8a, 8b that branch corresponding to the
usage-side air-conditioning apparatuses 3a, 3b.
[0052] <Heat-Source-Side Air-Conditioning Apparatus>
[0053] The heat-source-side air-conditioning apparatus 2, as
described above, is connected to the usage-side air-conditioning
apparatuses 3a, 3b via the refrigerant interconnection pipes 11,
12, configuring part of the refrigerant circuit 10.
[0054] The heat-source-side air-conditioning apparatus 2 mainly has
a compressor 21, a switching mechanism 23, and a heat-source-side
heat exchanger 24.
[0055] The compressor 21 is a mechanism to compress the
refrigerant, and in this embodiment, a sealed compressor is used in
which a rotary, scroll, or other type of positive displacement
compression element (not shown) accommodated in a casing (not
shown) is driven by a compressor motor 22 also accommodated in the
casing.
[0056] The switching mechanism 23 is a four-way switching valve
capable of switching between an air-cooling operation state in
which the heat-source-side heat exchanger 24 is caused to function
as a heat radiator of the refrigerant, and an air-warming operation
state in which the heat-source-side heat exchanger 24 is caused to
function as an evaporator of the refrigerant. In this embodiment,
the air-cooling operation state is a switched state in which a
discharge side of the compressor 21 and a gas side of the
heat-source-side heat exchanger 24 are allowed to communicate, and
the gas refrigerant interconnection pipe 12 and an intake side of
the compressor 21 are allowed to communicate (refer to the solid
lines of the switching mechanism 23 in FIG. 1). The air-warming
operation state is a switched state in which the discharge side of
the compressor 21 and the gas refrigerant interconnection pipe 12
are allowed to communicate, and the gas side of the
heat-source-side heat exchanger 24 and the intake side of the
compressor 21 are allowed to communicate (refer to the dashed lines
of the switching mechanism 23 in FIG. 1). The switching mechanism
23 is not limited to a four-way switching valve. For example, the
switching mechanism 23 may be configured so as to have a function
to switch the direction of refrigerant flow, similar to that
described above, by a technique such as combining a plurality of
electromagnetic valves.
[0057] The heat-source-side heat exchanger 24 functions as a heat
radiator or an evaporator of the refrigerant by conducting heat
exchange between the refrigerant and the outdoor air (OA). The
outdoor air (OA), which exchanges heat with the refrigerant in the
heat-source-side heat exchanger 24, is supplied to the
heat-source-side heat exchanger 24 by a heat-source-side fan 25
driven by a heat-source-side fan motor 26.
[0058] <Usage-Side Air-Conditioning Apparatuses>
[0059] The usage-side air-conditioning apparatuses 3a, 3b, as
described above, are connected to the heat-source-side
air-conditioning apparatus 2 via the refrigerant interconnection
pipes 11, 12, configuring part of the refrigerant circuit 10.
Additionally, the usage-side air-conditioning apparatuses 3a, 3b,
as described above, are designed so as to be able to exchange air
with the air-conditioned spaces S1, S2 and/or the outsides of the
air-conditioned spaces S1, S2 via the air ducts 5 (5a, 5b), 6a, 6b,
7a, 7b, 8 (8a, 8b). In the following description, the configuration
of the usage-side air-conditioning apparatus 3a is described, and
description of the configuration of the usage-side air-conditioning
apparatus 3b, in which the additional letter "a" is replaced by "b"
for each component, is omitted.
[0060] The usage-side air-conditioning apparatus 3a mainly has a
casing 31a, a usage-side expansion mechanism 32a, a usage-side heat
exchanger 33a, a total heat exchanger 34a, a first air supply
blower 35a, a first air exhaust blower 37a, and a refrigerant
leakage detection device 48a.
[0061] The casing 31a is installed in the usage-side installation
space S3, and various ducts 5a, 6a, 7a, 8a are connected to the
casing 31a. A space to accommodate the usage-side heat exchanger
33a and the like is formed in the casing 31a.
[0062] The usage-side expansion mechanism 32a is an electric
expansion valve that can, by performing opening degree control,
vary the flow rate of the refrigerant flowing through the
usage-side heat exchanger 33a. The usage-side expansion mechanism
32a is provided inside the casing 31a. One end of the usage-side
expansion mechanism 32a is connected to a liquid side of the
usage-side heat exchanger 33a, and another end of the usage-side
expansion mechanism 32a is connected to the liquid refrigerant
interconnection pipe 11 via a joint 13a. The joint 13a is a pipe
joint to connect the usage-side heat exchanger 33a to the
refrigerant interconnection pipes 11, 12, and in this embodiment,
is provided inside the casing 31a.
[0063] The usage-side heat exchanger 33a is a heat exchanger to
cool or heat the air (RA and/or OA) in the casing 31a by means of
the refrigerant supplied from the heat-source-side air-conditioning
apparatus 2. The usage-side heat exchanger 33a is provided inside
the casing 31a. The usage-side heat exchanger 33a is connected to
the heat-source-side air-conditioning apparatus 2 via the
refrigerant interconnection pipes 11, 12. A liquid side of the
usage-side heat exchanger 33a is connected to the liquid
refrigerant interconnection pipe 11 via the usage-side expansion
mechanism 32a and the joint 13a, and a gas side of the usage-side
heat exchanger 33a is connected to the gas refrigerant
interconnection pipe 12 via a joint 14a. The joint 14a is a pipe
joint to connect the usage-side heat exchanger 33a to the gas
refrigerant interconnection pipe 12, and in this embodiment, is
provided inside the casing 31a.
[0064] The total heat exchanger 34a conducts heat exchange between
the outdoor air (OA) and the room air (RA). In this embodiment, a
heat exchanger that causes sensible heat and latent heat to be
exchanged simultaneously between the two types of air (OA and RA)
is used as the total heat exchanger 34a. The total heat exchanger
34a is provided inside the casing 31a, and the space inside the
casing 31a is divided by the total heat exchanger 34a into an air
supply passage 42a and an outtake passage 43a on the side nearer to
the air-conditioned space S1, and an intake passage 41a and an air
exhaust passage 44a on the side farther from the air-conditioned
space S1. The intake passage 41a communicates with the intake duct
5 (5a), the air supply passage 42a communicates with the air supply
duct 6a, the outtake passage 43a communicates with the outtake duct
7a, and the air exhaust passage 44a communicates with the air
exhaust duct 8 (8a). The usage-side expansion mechanism 32a and the
usage-side heat exchanger 33a are provided inside the air supply
passage 42a within the space inside the casing 31a, and in this
embodiment, the joints 13a, 14a are also provided inside the air
supply passage 42a. Therefore, the usage-side heat exchanger 33a is
designed to cool or heat the air inside the air supply passage 42a.
Additionally, the casing 31a is provided with an air return
regulation mechanism 45a composed of a communication passage that
allows communication between the air supply passage 42a and the
outtake passage 43a, and an air damper placed in this communication
passage. The air return regulation mechanism 45a is capable of
switching between an air supply-outtake communication state of
allowing the outtake passage 43a to communicate with the air supply
passage 42a by opening the air damper, and an air supply-outtake
non-communication state of not allowing the outtake passage 43a to
communicate with the air supply passage 42a by closing the air
damper.
[0065] The first air supply blower 35a is a fan provided so as to
be able to take the outdoor air (OA) in from outside the
air-conditioned space S1, and supply the supply air (SA) to the
air-conditioned space S1. The first air supply blower 35a is
provided inside the air supply passage 42a, and an outlet of this
blower is connected to the air supply duct 6a. The first air supply
blower 35a is designed to be driven by a first air supply blower
motor 36a.
[0066] The first air exhaust blower 37a is a fan provided so as to
be able to take the room air (RA) in from the air-conditioned space
S1, and exhaust the exhaust air (EA) out of the air-conditioned
space S1. The first air exhaust blower 37a is provided inside the
air exhaust passage 44a, and an outlet of this blower is connected
to the air exhaust duct 8 (8a). The first air exhaust blower 37a is
designed to be driven by a first air exhaust blower motor 38a.
Additionally, a backflow prevention mechanism 46a composed of an
air damper is provided to the outlet of the first air exhaust
blower 37a. The air damper of the backflow prevention mechanism 46a
is designed to be opened in order to exhaust the exhaust air (EA)
to the air exhaust duct 8 when the first air exhaust blower 37a is
operating, and closed in order to prevent backflow of the exhaust
air (EA) from the air exhaust duct 8 when the first air exhaust
blower 37a has stopped operating. The backflow prevention mechanism
46a may be provided to the air exhaust branch duct 8a rather than
the outlet of the first air exhaust blower 37a. The backflow
prevention mechanism 46a may not be provided when there is
guaranteed to be no backflow of the exhaust air (EA), such as cases
in which a blower is provided to the air exhaust duct 8.
[0067] When the above-described air passages 41a, 42a, 43a, 44a,
mechanisms 45a, 46a, and blowers 35a, 37a are connected with the
air ducts 5 (5a), 6a, 6b, 7a, 7b, 8 (8a), an air supply/exhaust
mechanism of the usage-side air-conditioning apparatus 3a is
configured, which takes the room air (RA) into the casing 31a from
the air-conditioned space S1, takes the outdoor air (OA) into the
casing 31a from outside the air-conditioned space S1, supplies the
air in the casing 31a as supply air (SA) to the air-conditioned
space S1, and exhausts the air in the casing 31a as exhaust air
(EA) out of the air-conditioned space S1.
[0068] The refrigerant leakage detection device 48a is a device to
detect refrigerant. The refrigerant leakage detection device 48a is
provided inside the casing 31a. In this embodiment, the refrigerant
leakage detection device 48a is provided inside the air supply
passage 42a in which the usage-side heat exchanger 33a (in this
embodiment, the joints 13a, 14a and/or the usage-side expansion
mechanism 32a) is placed. Furthermore, in this embodiment, the
refrigerant leakage detection device 48a is provided either to a
lower part (when the refrigerant is denser than air) of the casing
31a (in this embodiment, the air supply passage 42a) or an upper
part (when the refrigerant is less dense than air) of the casing
31a (in this embodiment, the air supply passage 42a). FIG. 1 shows
a case in which the refrigerant leakage detection device 48a is
provided to the lower part of the casing 31a.
[0069] <Control Device>
[0070] The air-conditioning apparatus 1 has a control device 9 to
perform operation control on the heat-source-side air-conditioning
apparatus 2 and the usage-side air-conditioning apparatuses 3a, 3b,
etc. The control device 9 mainly has a heat-source-side control
device 92 to control the actions of the components (compressor,
etc.) configuring the heat-source-side air-conditioning apparatus
2, and usage-side control devices 93a, 93b to control the actions
of the components (fans, refrigerant leakage detection devices,
etc.) configuring the usage-side air-conditioning apparatuses 3a,
3b. The heat-source-side control device 92, which is provided to
the heat-source-side air-conditioning apparatus 2, has a
microcomputer and/or a memory, etc. for performing control on the
heat-source-side air-conditioning apparatus 2. The usage-side
control devices 93a, 93b, which are provided to the usage-side
air-conditioning apparatuses 3a, 3b, have microcomputers and/or
memories, etc. for performing control on the usage-side
air-conditioning apparatuses 3a, 3b. The heat-source-side control
device 92 and the usage-side control devices 93a, 93b are connected
so as to be capable of exchanging, for example, control signals via
a transmission line, and the control device 9 of the
air-conditioning apparatus 1 is thereby configured. In this
embodiment, the control devices 92, 93a, 93b are connected via a
transmission line, but are not limited to being connected in this
manner and may be connected wirelessly or by another connection
method.
[0071] (2) Operations
[0072] In the air-conditioning apparatus 1 having the configuration
described above, the following operations are performed. Operation
controls of the air-conditioning apparatus 1 described below are
performed by the control device 9.
[0073] <Normal Operation>
[0074] In normal operation, an operation is performed such that the
outdoor air (OA) is taken into the casings 31a, 31b from outside
the air-conditioned spaces S1, S2, the air is cooled or heated in
the usage-side heat exchangers 33a, 33b and then supplied as supply
air (SA) to the air-conditioned spaces S1, S2, the room air (RA) is
taken into the casings 31a, 31b from the air-conditioned spaces S1,
S2, the air exchanges heat with the outdoor air (OA) in the total
heat exchangers 34a, 34b, and then which the air is exhausted as
exhaust air (EA) out of the air-conditioned spaces S1, S2, as shown
in FIG. 1. Specifically, operation control such as the following is
performed on the components of the air-conditioning apparatus
1.
[0075] When air is supplied as supply air (SA) to the
air-conditioned spaces S1, S2 after being cooled in the usage-side
heat exchangers 33a, 33b, in the heat-source-side air-conditioning
apparatus 2, the switching mechanism 23 is switched to the
air-cooling operation state (the state shown by the solid lines of
the switching mechanism 23 in FIG. 1), and the compressor 21 and
the heat-source-side fan 25 are driven. High-pressure gas
refrigerant discharged from the compressor 21 is thereby sent
through the switching mechanism 23 to the heat-source-side heat
exchanger 24 functioning as a heat radiator of the refrigerant. The
high-pressure gas refrigerant sent to the heat-source-side heat
exchanger 24 is condensed to high-pressure liquid refrigerant due
to being cooled by heat exchange with the outdoor air (OA) supplied
by the heat-source-side fan 25 in the heat-source-side heat
exchanger 24. This high-pressure liquid refrigerant is sent to the
usage-side air-conditioning apparatuses 3a, 3b via the liquid
refrigerant interconnection pipe 11. The high-pressure liquid
refrigerant sent to the usage-side air-conditioning apparatuses 3a,
3b is decompressed to low-pressure, gas-liquid two-phase
refrigerant by the usage-side expansion mechanisms 32a, 32b. This
low-pressure, gas-liquid two-phase refrigerant is sent to the
usage-side heat exchangers 33a, 33b functioning as evaporators of
the refrigerant. The low-pressure, gas-liquid two-phase refrigerant
sent to the usage-side heat exchangers 33a, 33b is evaporated in
the usage-side heat exchangers 33a, 33b to low-pressure gas
refrigerant due to being heated by heat exchange with the air
inside the air supply passages 42a, 42b. This low-pressure gas
refrigerant is sent to the heat-source-side air-conditioning
apparatus 2 via the gas refrigerant interconnection pipe 12. The
low-pressure gas refrigerant sent to the heat-source-side
air-conditioning apparatus 2 is drawn into the compressor 21 via
the switching mechanism 23.
[0076] When air is supplied as supply air (SA) to the
air-conditioned spaces S1, S2 after being heated in the usage-side
heat exchangers 33a, 33b, in the heat-source-side air-conditioning
apparatus 2, the switching mechanism 23 is switched to the
air-warming operation state (the state shown by the dashed lines of
the switching mechanism 23 in FIG. 1), and the compressor 21 and
the heat-source-side fan 25 are driven. High-pressure gas
refrigerant discharged from the compressor 21 is thereby sent to
the usage-side air-conditioning apparatuses 3a, 3b via the
switching mechanism 23 and the gas refrigerant interconnection pipe
12. The high-pressure gas refrigerant sent to the usage-side
air-conditioning apparatuses 3a, 3b is sent to the usage-side heat
exchangers 33a, 33b functioning as heat radiators of the
refrigerant. The high-pressure gas refrigerant sent to the
usage-side heat exchangers 33a, 33b is condensed in the usage-side
heat exchangers 33a, 33b to high-pressure liquid refrigerant due to
being cooled by heat exchange with the air inside the air supply
passages 42a, 42b. This high-pressure liquid refrigerant
decompressed by the usage-side expansion mechanisms 32a, 32b. The
refrigerant decompressed by the usage-side expansion mechanisms
32a, 32b is sent to the heat-source-side air-conditioning apparatus
2 via the liquid refrigerant interconnection pipe 11. The
refrigerant sent to the heat-source-side air-conditioning apparatus
2 is sent to the heat-source-side heat exchanger 24 functioning as
an evaporator of the refrigerant. The refrigerant sent to the
heat-source-side heat exchanger 24 is evaporated in the
heat-source-side heat exchanger 24 to low-pressure gas refrigerant
due to being heated by heat exchange with the outdoor air (OA)
supplied by the heat-source-side fan 25. This low-pressure gas
refrigerant is drawn into the compressor 21 via the switching
mechanism 23.
[0077] At this time, in the usage-side air-conditioning apparatuses
3a, 3b, the backflow prevention mechanisms 46a, 46b are opened, and
the first air supply blowers 35a, 35b and the first air exhaust
blowers 37a, 37b are driven. This causes outdoor air (OA) to be
taken through the intake duct 5 (5a, 5b) into the intake passages
41a, 41b of the casings 31a, 31b from outside the air-conditioned
spaces S1, S2, and room air (RA) to be taken through the outtake
ducts 7a, 7b into the outtake passages 43a, 43b of the casings 31a,
31b from the air-conditioned spaces S1, S2. The outdoor air (OA)
and the room air (RA) taken into the casings 31a, 31b are caused to
exchange heat in the total heat exchangers 34a, 34b, and are
respectively sent to the air supply passage 42a and the air exhaust
passage 44a. In this embodiment, when the air return regulation
mechanisms 45a, 45b are switched to the air supply-outtake
communication state (refer to the air return regulation mechanisms
45a, 45b in FIG. 1), some of the room air (RA) taken into the
casings 31a, 31b is sent to the air supply passage 42a in
accordance with the opening degrees of the air dampers of the air
return regulation mechanisms 45a, 45b, and this air merges with the
outdoor air (OA) which has undergone heat exchange in the total
heat exchangers 34a, 34b. When the air return regulation mechanisms
45a, 45b are switched to the air supply-outtake non-communication
state, all of the room air (RA) taken into the casings 31a, 31b
undergoes heat exchange with all of the outdoor air (OA) taken into
the casings 31a, 31b. The room air (RA) sent to the air exhaust
passages 44a, 44b is then exhausted as exhaust air (EA) out of the
air-conditioned spaces S1, S2 through the first air exhaust blowers
37a, 37b and the air exhaust duct 8 (8a, 8b). The outdoor air (OA)
or the outdoor air (OA) including room air (RA) sent to the air
supply passages 42a, 42b is cooled or heated in the usage-side heat
exchangers 33a, 33b by the refrigerant supplied from the
heat-source-side air-conditioning apparatus 2 through the liquid
refrigerant interconnection pipe 11. The outdoor air (OA) or the
outdoor air (OA) including room air (RA) cooled or heated in the
usage-side heat exchangers 33a, 33b is supplied as supply air (SA)
to the air-conditioned spaces S1, S2 through the first air supply
blowers 35a, 35b and the air supply ducts 6a, 6b.
[0078] <Refrigerant Exhaust Operation>
[0079] During the normal operation described above, when
refrigerant leaks in the usage-side air-conditioning apparatuses
3a, 3b, the leaked refrigerant is supplied to the air-conditioned
spaces S1, S2, and there is a risk of ignition accidents (when the
refrigerant is slightly flammable or flammable) or poisoning
accidents (when the refrigerant is toxic) occurring. In view of
this, when the refrigerant leakage detection devices 48a, 48b
detect refrigerant, a refrigerant exhaust operation is performed to
exhaust refrigerant together with the air in the casings 31a, 31b
out of the air-conditioned spaces S1, S2, by means of the air
supply/exhaust mechanisms. In this embodiment, the refrigerant
exhaust operation is performed by operating the first air exhaust
blowers 37a, 37b configuring the air supply/exhaust mechanisms.
[0080] For example, supposing a case in which refrigerant has
leaked in the usage-side air-conditioning apparatus 3b (i.e., the
refrigerant leakage detection device 48b has detected refrigerant),
the first air exhaust blower 37b is operated in the usage-side
air-conditioning apparatus 3b as shown in FIG. 3. The leaked
refrigerant, along with the air in the casing 31b, is thereby
passed through the section of the total heat exchanger 34b
communicating with the outtake passage 43b and the air exhaust
passage 44b, and exhausted to the air exhaust duct 8 (8b). At this
time, because the usage-side heat exchanger 33b and the joints 13b,
14b, which have a high possibility of refrigerant leakage, are
placed in the air supply passage 42b, the air supply passage 42b
and the outtake passage 43b are allowed to communicate and
refrigerant exhaust is facilitated by putting the air return
regulation mechanism 45b in the air supply-outtake communication
state. The first air supply blower 35b is stopped to prevent the
leaked refrigerant from being supplied to the air-conditioned space
S2. In this embodiment, when the first air supply blower 35b is
stopped and the first air exhaust blower 37b is operated, room air
(RA) is taken into the casing 31b from the air-conditioned space
S2, outdoor air (OA) is taken into the casing 31b from outside the
air-conditioned space S2, and these two types of air (RA and OA)
are therefore exhausted to the air exhaust duct 8 (8b) along with
the leaked refrigerant. In the heat-source-side air-conditioning
apparatus 2, refrigerant is prevented from being supplied from the
heat-source-side air-conditioning apparatus 2 to the usage-side
air-conditioning apparatus 3b, for example, due to the compressor
21 being stopped. In the usage-side air-conditioning apparatus 3a,
in which refrigerant is not leaking, the refrigerant that leaked in
the usage-side air-conditioning apparatus 3b is prevented from
flowing back to the casing 31a through the air exhaust duct 8 (8a)
by closing the backflow prevention mechanism 46a.
[0081] (3) Characteristics
[0082] The usage-side air-conditioning apparatuses 3a, 3b of the
present embodiment and the air-conditioning apparatus 1 provided
with the same have characteristics such as the following.
[0083] <A>
[0084] In this embodiment, as described above, in the usage-side
air-conditioning apparatuses 3a, 3b having the ventilating
air-condition function and the air-conditioning apparatus 1
provided with the same, when the refrigerant leakage detection
devices 48a, 48b detect refrigerant, the refrigerant exhaust
operation is performed by the air supply/exhaust mechanisms to
exhaust the refrigerant along with the air in the casings 31a, 31b
out of the air-conditioned spaces S1, S2. Particularly, in this
embodiment, the refrigerant exhaust operation is performed by
operating the first air exhaust blowers 37a, 37b. Additionally, in
this embodiment, the air-conditioning apparatus 1 is configured by
connecting the heat-source-side air-conditioning apparatus 2 and
the plurality (two in this embodiment) of usage-side
air-conditioning apparatuses 3a, 3b.
[0085] In this embodiment, when refrigerant leaks, it is thereby
possible to ensure that the leaked refrigerant is quickly exhausted
and not supplied to the air-conditioned spaces S1, S2, using the
air supply/exhaust mechanisms (in this embodiment, by operating the
first air exhaust blowers 37a, 37b). Additionally, in this
embodiment, when refrigerant has leaked in any of the plurality of
usage-side air-conditioning apparatuses 3a, 3b, it is possible to
ensure that the leaked refrigerant is quickly exhausted using the
air supply/exhaust mechanism of the usage-side air-conditioning
apparatus 3a or 3b in which the refrigerant has leaked, and that
the refrigerant is not supplied to the air-conditioned space S1 or
S2 that is being air-conditioned by the usage-side air-conditioning
apparatus 3a or 3b in which the refrigerant has leaked.
[0086] When the refrigerant is slightly flammable or flammable, the
occurrence of ignition accidents in the air-conditioned spaces S1,
S2 can be suppressed. When the refrigerant is toxic, the occurrence
of poisoning accidents in the air-conditioned spaces S1, S2 can be
suppressed. The occurrence of oxygen deficiency accidents in the
air-conditioned spaces S1, S2 can be suppressed even when the
refrigerant is not slightly flammable, flammable, or toxic.
[0087] <B>
[0088] In this embodiment, as described above, the joints 13a, 13b,
14a, 14b connecting the usage-side heat exchangers 33a, 33b to the
refrigerant interconnection pipes 11, 12 are provided inside the
casings 31a, 31b. Therefore, when refrigerant leaks from the joints
13a, 13b, 14a, 14b connecting the usage-side heat exchangers 33a,
33b to the refrigerant interconnection pipes 11, 12, the leakage is
inside the casings 31a, 31b.
[0089] It is thereby possible in this embodiment to quickly detect
the refrigerant when the refrigerant has leaked, and to quickly
exhaust the leaked refrigerant.
[0090] <C>
[0091] In this embodiment, as described above, when the refrigerant
is denser than air, the refrigerant leakage detection devices 48a,
48b are provided in the lower parts of the casings 31a, 31b.
[0092] It is thereby possible in this embodiment to quickly detect
the refrigerant utilizing the tendency of the refrigerant denser
than air to accumulate downward.
[0093] In this embodiment, as described above, when the refrigerant
is less dense than air, the refrigerant leakage detection devices
48a, 48b are provided in the upper parts of the casings 31a,
31b.
[0094] It is thereby possible in this embodiment to quickly detect
the refrigerant utilizing the tendency of the refrigerant less
dense than air to accumulate upward.
[0095] (4) Modifications
[0096] In the above-described usage-side air-conditioning
apparatuses 3a, 3b and the air-conditioning apparatus 1 provided
with the same (see FIGS. 1 to 3), the joints 13a, 13b, 14a, 14b
connecting the usage-side heat exchangers 33a, 33b to the
refrigerant interconnection pipes are provided inside the casings
31a, 31b, but there are also cases in which the joints 13a, 13b,
14a, 14b are provided outside of the casings 31a, 31b, as shown in
FIG. 4. In these cases, when refrigerant leaks from the joints 13a,
13b, 14a, 14b, the leakage occurs in the usage-side installation
spaces S3, S4 in which the casings 31a, 31b of the usage-side
air-conditioning apparatuses 3a, 3b are installed.
[0097] In view of this, in this modification, the usage-side
air-conditioning apparatuses 3a, 3b are provided with
inside-outside communication mechanisms 47a, 47b, which are capable
of switching between an inside-outside communication state of
allowing the usage-side installation spaces S3, S4 and the
interiors of the casings 31a, 31b to communicate, and an
inside-outside non-communication state of not allowing the
usage-side installation spaces S3, S4 and the interiors of the
casings 31a, 31b to communicate, as shown in FIGS. 4 and 5, and the
refrigerant exhaust operation is performed by putting the
inside-outside communication mechanisms 47a, 47b in the
inside-outside communication state.
[0098] The following is a description, using FIGS. 2, 4, and 5, of
the configurations and operations of the usage-side
air-conditioning apparatuses 3a, 3b according to the present
modification and the air-conditioning apparatus 1 provided with the
same, focusing on the differences with the above-described
usage-side air-conditioning apparatuses 3a, 3b and the
air-conditioning apparatus 1 provided with the same (see FIGS. 1 to
3).
[0099] Firstly, the configurations of the usage-side
air-conditioning apparatuses 3a, 3b according to the present
modification and the air-conditioning apparatus 1 provided with the
same are described. In this modification, the overall configuration
of the air-conditioning apparatus 1 according to the present
modification, and the configuration of the heat-source-side
air-conditioning apparatus 2 according to the present modification,
are similar to the above-described configuration of the
air-conditioning apparatus 1 (see FIG. 1) and the configuration of
the heat-source-side air-conditioning apparatus 2 (see FIG. 1), and
are therefore not described here.
[0100] The configurations of the usage-side air-conditioning
apparatuses 3a, 3b according to the present modification differ
from the configurations of the usage-side air-conditioning
apparatuses 3a, 3b described above (see FIG. 1) in that the joints
13a, 13b, 14a, 14b connecting the usage-side heat exchangers 33a,
33b to the refrigerant interconnection pipes are provided outside
of the casings 31a, 31b, as shown in FIG. 4. The casings 31a, 31b
are also provided with the inside-outside communication mechanisms
47a, 47b as described above. The inside-outside communication
mechanisms 47a, 47b are composed of communication passages to allow
communication between the air supply passages 42a, 42b and the
usage-side installation spaces S3, S4, and air dampers placed in
these communication passages. The inside-outside communication
mechanisms 47a, 47b are capable of switching between an
inside-outside communication state of allowing the air supply
passages 42a, 42b and the usage-side installation spaces S3, S4 to
communicate by opening the air dampers, and an inside-outside
non-communication state of not allowing the air supply passages
42a, 42b and the usage-side installation spaces S3, S4 to
communicate. Also provided to the outsides of the casings 31a, 31b
are refrigerant leakage detection devices 49a, 49b to detect
refrigerant that has leaked in the usage-side installation spaces
S3, S4. Also provided to the usage-side installation spaces S3, S4
are installation space inside-outside communication mechanisms 39a,
39b composed of communication passages communicating with the
outsides of the usage-side installation spaces S3, S4 and air
dampers placed in these communication passages. The installation
space inside-outside communication mechanisms 39a, 39b are capable
of switching between an installation space inside-outside
communication state of allowing the usage-side installation spaces
S3, S4 and the exteriors thereof to communicate by opening the air
dampers, and an installation space inside-outside non-communication
state of not allowing the usage-side installation spaces S3, S4 and
the exteriors thereof to communicate by closing the air dampers.
The inside-outside communication mechanisms 47a, 47b and the
installation space inside-outside communication mechanisms 39a,
39b, together with the air passages 41a, 42a, 43a, 44a, the
mechanisms 45a, 46a, and the air blowers 35a, 37a, configure the
air supply/exhaust mechanisms of the usage-side air-conditioning
apparatuses 3a, 3b according to the present modification. The
configurations of the usage-side air-conditioning apparatuses 3a,
3b according to the present modification are otherwise similar to
the configurations of the usage-side air-conditioning apparatuses
3a, 3b described above (see FIG. 1), and are therefore not
described here.
[0101] The configuration of a control device 9 according to the
present modification is similar to the configuration of the control
device 9 described above (see FIG. 2), aside from the feature that
operation control is performed on the newly provided inside-outside
communication mechanisms 47a, 47b, refrigerant leakage detection
devices 49a, 49b, and installation space inside-outside
communication mechanisms 39a, 39b; and is therefore not illustrated
or described here.
[0102] Next, the operations of the usage-side air-conditioning
apparatuses 3a, 3b according to the present modification and the
air-conditioning apparatus 1 provided with the same are described.
In this modification, the operation of the heat-source-side
air-conditioning apparatus 2 of the air-conditioning apparatus 1
according to the present modification is similar to the operation
of the heat-source-side air-conditioning apparatus 2 of the
air-conditioning apparatus 1 described above, and is therefore not
described here.
[0103] During normal operation, the operation of the usage-side
air-conditioning apparatuses 3a, 3b according to the present
modification involves putting the inside-outside communication
mechanisms 47a, 47b into the inside-outside non-communication state
and the installation space inside-outside communication mechanisms
39a, 39b into the installation space inside-outside
non-communication state as shown in FIG. 4, and the resulting
operation is substantially similar to the normal operation of the
usage-side air-conditioning apparatuses 3a, 3b described above (see
FIG. 1).
[0104] However, the refrigerant exhaust operation of the usage-side
air-conditioning apparatuses 3a, 3b according to the present
modification differs from the refrigerant exhaust operation of the
usage-side air-conditioning apparatuses 3a, 3b described above (see
FIG. 3) in that the inside-outside communication mechanisms 47a,
47b are put into the inside-outside communication state, as
described above.
[0105] For example, supposing that refrigerant has leaked in the
usage-side air-conditioning apparatus 3b (specifically, that the
refrigerant leakage detection devices 48b, 49b have detected
refrigerant), in the usage-side air-conditioning apparatus 3b, the
inside-outside communication mechanism 47b is put into the
inside-outside communication state and the first air exhaust blower
37b is operated, as shown in FIG. 5. The leaked refrigerant, along
with the air in the casing 31b is thereby passed through the
section of the total heat exchanger 34b communicating with the
outtake passage 43b and the air exhaust passage 44b, and exhausted
to the air exhaust duct 8 (8b). At this time, because the joints
13b, 14b, which have a high possibility of refrigerant leakage, are
placed outside the casing 31b (the usage-side installation space
S4), refrigerant sometimes leaks into the usage-side installation
space S4, but because the air supply passage 42b of the casing 31b
and the usage-side installation space S4 are allowed to communicate
by putting the inside-outside communication mechanism 47b into the
inside-outside communication state as described above, the
refrigerant leaked into the usage-side installation space S4 is
guided into the casing 31b using the inside-outside communication
mechanism 47b, and along with the air in the casing 31b, the
refrigerant is passed through the section of the total heat
exchanger 34b communicating with the outtake passage 43b and the
air exhaust passage 44b and exhausted to the air exhaust duct 8
(8b). Additionally, the installation space inside-outside
communication mechanisms 39a, 39b are put into the installation
space inside-outside communication state, making it easier for air
to be guided from the usage-side installation space S4 into the air
supply passage 42b. Other operative actions in the refrigerant
exhaust operation according to the present modification are similar
to those of the refrigerant exhaust operation in the usage-side
air-conditioning apparatuses 3a, 3b described above (see FIG. 3),
and are therefore not described here.
[0106] In such usage-side air-conditioning apparatuses 3a, 3b
according to the present modification and the air-conditioning
apparatus 1 provided with the same, because the joints 13a, 13b,
14a, 14b are provided outside the casings 31a, 31b, the operational
effects derived from providing the joints 13a, 13b, 14a, 14b inside
the casings 31a, 31b cannot be achieved, but in other aspects, the
same operational effects can be achieved as those of the usage-side
air-conditioning apparatuses 3a, 3b described above and the
air-conditioning apparatus 1 provided with the same (see FIGS. 1 to
3).
[0107] Additionally, in this modification, communication between
the usage-side installation spaces S3, S4 and the casing interiors
can be allowed by the inside-outside communication mechanisms 47a,
47b, regardless of the joints 13a, 13b, 14a, 14b being provided
outside the casings 31a, 31b. Therefore, in this modification, when
refrigerant has leaked, the refrigerant leaked into the usage-side
installation spaces S3, S4 can be quickly exhausted while being
guided into the casings 31a, 31b and can be prevented from being
supplied to the air-conditioned spaces S1, S2, using the air
supply/exhaust mechanisms including the inside-outside
communication mechanisms 47a, 47b.
Second Embodiment
[0108] (1) Configuration
[0109] FIG. 6 is an overall configuration diagram of usage-side
air-conditioning apparatuses 3a, 3b according to a second
embodiment of the present invention, and an air-conditioning
apparatus 1 provided with the same. FIG. 7 is a control block
diagram of the air-conditioning apparatus 1 in the second
embodiment.
[0110] <Overall>
[0111] The air-conditioning apparatus 1, which is an
air-conditioning ventilation system having a ventilating
air-condition function for ventilating and air-conditioning the
interior of a room, mainly has a heat-source-side air-conditioning
apparatus 2, and a plurality (two in this embodiment) of usage-side
air-conditioning apparatuses 3a, 3b.
[0112] The air-conditioning apparatus 1 has a refrigerant circuit
10 through which refrigerant circulates. The refrigerant circuit 10
is configured by connecting the heat-source-side air-conditioning
apparatus 2 to the usage-side air-conditioning apparatuses 3a, 3b.
In this embodiment, the heat-source-side air-conditioning apparatus
2 is installed in a location such as on the roof of a building, and
the usage-side air-conditioning apparatuses 3a, 3b are installed in
usage-side installation spaces (in this embodiment, usage-side
installation spaces S3, S4), such as a machine room of the building
or a space above the ceiling, in correspondence with
air-conditioned spaces (in this embodiment, air-conditioned spaces
S1, S2) that are ventilated and air-conditioned. The
heat-source-side air-conditioning apparatus 2 and the usage-side
air-conditioning apparatuses 3a, 3b are connected via refrigerant
interconnection pipes 11, 12, thereby configuring the refrigerant
circuit 10. The refrigerant sealed within the refrigerant circuit
10 is a slightly flammable refrigerant such as R32, a flammable
refrigerant such as propane, or a toxic refrigerant such as
ammonia.
[0113] The air-conditioning apparatus 1 has a plurality of air
ducts. In this embodiment, the air-conditioning apparatus 1 has an
intake duct 5 for taking outdoor air (OA) into the usage-side
air-conditioning apparatuses 3a, 3b from outside the
air-conditioned spaces S1, S2, air supply ducts 6a, 6b for
supplying supply air (SA) from the usage-side air-conditioning
apparatuses 3a, 3b to the air-conditioned spaces S1, S2, and
outtake ducts 7a, 7b for taking room air (RA) from the
air-conditioned spaces S1, S2 into the corresponding usage-side
air-conditioning apparatuses 3a, 3b, whereby air can be exchanged
between the air-conditioned spaces S1, S2 and/or the outsides of
the air-conditioned spaces S1, S2 and the usage-side
air-conditioning apparatuses 3a, 3b. Also connected to the
air-conditioned spaces S1, S2 is an air exhaust duct 8 for
exhausting exhaust air (EA) out of the air-conditioned spaces S1,
S2. The intake duct 5 has intake branch ducts 5a, 5b that branch
corresponding to the usage-side air-conditioning apparatuses 3a,
3b, and the air exhaust duct 8 has air exhaust branch ducts 8a, 8b
that branch corresponding to the air-conditioned spaces S1, S2.
[0114] <Heat-Source-Side Air-Conditioning Apparatus>
[0115] The heat-source-side air-conditioning apparatus 2, as
described above, is connected to the usage-side air-conditioning
apparatuses 3a, 3b via the refrigerant interconnection pipes 11,
12, configuring part of the refrigerant circuit 10. The
configuration of the heat-source-side air-conditioning apparatus 2
according to the present embodiment is similar to the configuration
of the heat-source-side air-conditioning apparatus 2 of the first
embodiment described above (see FIG. 1), and is therefore not
described here.
[0116] <Usage-Side Air-Conditioning Apparatuses>
[0117] The usage-side air-conditioning apparatuses 3a, 3b, as
described above, are connected to the heat-source-side
air-conditioning apparatus 2 via the refrigerant interconnection
pipes 11, 12, configuring part of the refrigerant circuit 10.
Additionally, the usage-side air-conditioning apparatuses 3a, 3b,
as described above, are designed so as to be able to exchange air
with the air-conditioned spaces S1, S2 and/or the outsides of the
air-conditioned spaces S1, S2 via the air ducts 5 (5a, 5b), 6a, 6b,
7a, 7b. In the following description, the configuration of the
usage-side air-conditioning apparatus 3a is described, and
description of the configuration of the usage-side air-conditioning
apparatus 3b, in which the additional letter "a" is replaced by "b"
for each component, is omitted.
[0118] The usage-side air-conditioning apparatus 3a mainly has a
casing 31a, a usage-side expansion mechanism 32a, a usage-side heat
exchanger 33a, an air supply/exhaust blower 51a, and a refrigerant
leakage detection device 48a.
[0119] The casing 31a is installed in the usage-side installation
space S3, and various ducts 5a, 6a, 7a are connected to the casing
31a. An air supply passage 42a to accommodate the usage-side heat
exchanger 33a and the like is formed in the casing 31a.
[0120] The usage-side expansion mechanism 32a is an electric
expansion valve that can, by performing opening degree control,
vary the flow rate of the refrigerant flowing through the
usage-side heat exchanger 33a. The usage-side expansion mechanism
32a is provided inside the casing 31a (inside the air supply
passage 42a in this embodiment). One end of the usage-side
expansion mechanism 32a is connected to a liquid side of the
usage-side expansion mechanism 32a, and another end of the
usage-side expansion mechanism 32a is connected to the liquid
refrigerant interconnection pipe 11 via a joint 13a. The joint 13a
is a pipe joint to connect the usage-side heat exchanger 33a to the
refrigerant interconnection pipes 11, 12, and in this embodiment,
is provided inside the casing 31a (inside the air supply passage
42a in this embodiment).
[0121] The usage-side heat exchanger 33a is a heat exchanger to
cool or heat the air (RA and/or OA) in the casing 31a by means of
the refrigerant supplied from the heat-source-side air-conditioning
apparatus 2. The usage-side heat exchanger 33a is provided inside
the casing 31a (inside the air supply passage 42a in this
embodiment). The usage-side heat exchanger 33a is connected to the
heat-source-side air-conditioning apparatus 2 via the refrigerant
interconnection pipes 11, 12. A liquid side of the usage-side heat
exchanger 33a is connected to the liquid refrigerant
interconnection pipe 11 via the usage-side expansion mechanism 32a
and the joint 13a, and a gas side of the usage-side heat exchanger
33a is connected to the gas refrigerant interconnection pipe 12 via
a joint 14a. The joint 14a is a pipe joint to connect the
usage-side heat exchanger 33a to the gas refrigerant
interconnection pipe 12, and in this embodiment, is provided inside
the casing 31a (inside the air supply passage 42a in this
embodiment).
[0122] The air supply/exhaust blower Ma is a fan provided to be
capable of switching between an air supply state of taking room air
(RA) in from the air-conditioned space S1, taking outdoor air (OA)
in from outside the air-conditioned space S1, and supplying supply
air (SA) to the air-conditioned space S1, and an air exhaust state
of exhausting exhaust air (EA) out of the air-conditioned space S1.
The air supply/exhaust blower 51a is provided inside the air supply
passage 42a, and an outlet of this blower is connected to the air
supply duct 6a. The air supply/exhaust blower 51a is designed to be
driven by an air supply/exhaust blower motor 52a. An air supply
prevention mechanism 54a composed of an air damper is provided to
the outlet of the air supply/exhaust blower Ma. The air damper of
the air supply prevention mechanism 54a is opened when the air
supply/exhaust blower Ma is operated in the air supply state, and
closed when the air supply/exhaust blower Ma is operated in the air
exhaust state. The air supply prevention mechanism 54a may be
provided to the air supply duct 6a rather than to the outlet of the
air supply/exhaust blower Ma. One end of a bypass passage 53a is
connected to the outlet of the air supply/exhaust blower 51a in a
position on an upstream side of the air supply prevention mechanism
54a. Another end of the bypass passage 53a is connected to an inlet
for outdoor air (OA) in the casing 31a. A bypass opening/closing
mechanism 55a composed of an air damper is provided to the bypass
passage 53a. The air damper of the bypass opening/closing mechanism
55a is closed when the air supply/exhaust blower Ma is operated in
the air supply state, and is opened when the air supply/exhaust
blower 51a is operated in the air exhaust state. The bypass passage
53a including the bypass opening/closing mechanism 55a, rather than
connecting between the outlet of the air supply/exhaust blower 51a
and the inlet for outdoor air (OA) of the casing 31a, may be
provided so as to connect between the air supply duct 6a and the
intake duct 5 (5a). An intake prevention mechanism 56a composed of
an air damper is provided to the inlet for outdoor air (OA) of the
casing 31a in a position nearer to the air supply passage 42a than
the position where the other end of the bypass passage 53a is
connected. The air damper of the intake prevention mechanism 56a is
opened when the air supply/exhaust blower Ma is operated in the air
supply state, and closed when the air supply/exhaust blower Ma is
operated in the air exhaust state. An air return regulation
mechanism 57a composed of an air damper is provided to the inlet
for outdoor air (OA) of the casing 31a in a position nearer to the
intake duct 5 (5a) than the position where the other end of the
bypass passage 53a is connected. The intake prevention mechanism
56a and the air return regulation mechanism 57a may be provided to
the intake branch duct 5a rather than the inlet for outdoor air
(OA) of the casing 31a. Thus, the air supply/exhaust blower Ma can
be switched between operating in the air supply state and the air
exhaust state by the bypass passage 53a, the air supply prevention
mechanism 54a, the bypass opening/closing mechanism 55a, and the
intake prevention mechanism 56a. Specifically, the air
supply/exhaust blower 51a can be operated in the air supply state
by opening the air supply prevention mechanism 54a and the intake
prevention mechanism 56a and closing the bypass opening/closing
mechanism 55a, and the air supply/exhaust blower Ma can be operated
in the air exhaust state by closing the air supply prevention
mechanism 54a and the intake prevention mechanism 56a and opening
the bypass opening/closing mechanism 55a.
[0123] The above-described air passages 42a, 53a, mechanisms 54a,
55a, 56a, 57a, and blower Ma, when connected with the air ducts 5
(5a), 6a, 6b, 7a, 7b, configure an air supply/exhaust mechanism of
the usage-side air-conditioning apparatus 3a to take room air (RA)
into the casing 31a from the air-conditioned space S1, take outdoor
air (OA) into the casing 31a from outside the air-conditioned space
S1, supply the air inside the casing 31a as supply air (SA) to the
air-conditioned space S1, and exhaust the air inside the casing 31a
as exhaust air (EA) out of the air-conditioned space S1.
[0124] The refrigerant leakage detection device 48a is a device to
detect refrigerant. The refrigerant leakage detection device 48a is
provided inside the casing 31a. In this embodiment, the refrigerant
leakage detection device 48a is provided inside the air supply
passage 42a in which the usage-side heat exchanger 33a (in this
embodiment, the joints 13a, 14a and/or the usage-side expansion
mechanism 32a) is placed. Furthermore, in this embodiment, the
refrigerant leakage detection device 48a is provided either to a
lower part (when the refrigerant is denser than air) of the casing
31a (in this embodiment, the air supply passage 42a) or an upper
part (when the refrigerant is less dense than air) of the casing
31a (in this embodiment, the air supply passage 42a). FIG. 6 shows
a case in which the refrigerant leakage detection device 48a is
provided to the lower part of the casing 31a.
[0125] <Control Device>
[0126] The air-conditioning apparatus 1 has a control device 9 to
perform operation control on the heat-source-side air-conditioning
apparatus 2 and the usage-side air-conditioning apparatuses 3a, 3b,
etc. The control device 9 mainly has a heat-source-side control
device 92 to control the actions of the components (compressor,
etc.) configuring the heat-source-side air-conditioning apparatus
2, and usage-side control devices 93a, 93b to control the actions
of the components (fans, refrigerant leakage detection devices,
etc.) configuring the usage-side air-conditioning apparatuses 3a,
3b. The heat-source-side control device 92, which is provided to
the heat-source-side air-conditioning apparatus 2, has a
microcomputer and/or a memory, etc. for performing control on the
heat-source-side air-conditioning apparatus 2. The usage-side
control devices 93a, 93b, which are provided to the usage-side
air-conditioning apparatuses 3a, 3b, have microcomputers and/or
memories, etc. for performing control on the usage-side
air-conditioning apparatuses 3a, 3b. The heat-source-side control
device 92 and the usage-side control devices 93a, 93b are connected
so as to be capable of exchanging, for example, control signals via
a transmission line, and the control device 9 of the
air-conditioning apparatus 1 is thereby configured. In this
embodiment, the control devices 92, 93a, 93b are connected via a
transmission line, but are not limited to being connected in this
manner and may be connected wirelessly or by another connection
method.
[0127] (2) Actions
[0128] In the air-conditioning apparatus 1 having the configuration
described above, the following operations are performed. Operation
controls of the air-conditioning apparatus 1 described below are
performed by the control device 9.
[0129] <Normal Operation>
[0130] In normal operation, an operation is performed such that the
outdoor air (OA) is taken into the casings 31a, 31b from outside
the air-conditioned spaces S1, S2, room air (RA) is taken into the
casings 31a, 31b from the air-conditioned spaces S1, S2, and the
air is cooled or heated in the usage-side heat exchangers 33a, 33b
and then supplied as supply air (SA) to the air-conditioned spaces
S1, S2, as shown in FIG. 6. In this embodiment, exhaust air (EA) is
exhausted out of the air-conditioned spaces S1, S2 through the air
exhaust duct 8 (8a, 8b) connected to the air-conditioned spaces S1,
S2. Specifically, operation control such as the following is
performed on the components of the air-conditioning apparatus
1.
[0131] When air is supplied as supply air (SA) to the
air-conditioned spaces S1, S2 after being cooled in the usage-side
heat exchangers 33a, 33b, in the heat-source-side air-conditioning
apparatus 2, the switching mechanism 23 is switched to the
air-cooling operation state (the state shown by the solid lines of
the switching mechanism 23 in FIG. 6), and the compressor 21 and
the heat-source-side fan 25 are driven. When air is supplied as
supply air (SA) to the air-conditioned spaces S1, S2 after being
heated in the usage-side heat exchangers 33a, 33b, in the
heat-source-side air-conditioning apparatus 2, the switching
mechanism 23 is switched to the air-warming operation state (the
state shown by the dashed lines of the switching mechanism 23 in
FIG. 6), and the compressor 21 and the heat-source-side fan 25 are
driven. In this embodiment, the actions of the components of the
refrigerant circuit 10 etc. are the same as the actions of the
components of the refrigerant circuit 10, etc. of the first
embodiment and are therefore not described here.
[0132] In the usage-side air-conditioning apparatuses 3a, 3b at
this time, the air supply prevention mechanisms 54a, 54b, the
intake prevention mechanisms 56a, 56b, and the air return
regulation mechanisms 57a, 57b are opened, the bypass
opening/closing mechanism 55a is closed, and the air supply/exhaust
blowers 51a, 51b are driven. Specifically, the air supply/exhaust
blowers 51a, 51b are operated in the air supply state. Due to these
actions, outdoor air (OA) is taken into the air supply passages
42a, 42b of the casings 31a, 31b from outside the air-conditioned
spaces S1, S2 through the intake duct 5 (5a, 5b), and room air (RA)
is taken into the air supply passages 42a, 42b of the casings 31a,
31b from the air-conditioned spaces S1, S2 through the outtake
ducts 7a, 7b. The outdoor air (OA) and the room air (RA) taken into
the casings 31a, 31b is cooled or heated in the usage-side heat
exchangers 33a, 33b by refrigerant supplied from the
heat-source-side air-conditioning apparatus 2 through the liquid
refrigerant interconnection pipe 11. Having been cooled or heated
in the usage-side heat exchangers 33a, 33b, the outdoor air (OA) or
the outdoor air (OA) including room air (RA) is supplied as supply
air (SA) to the air-conditioned spaces S1, S2 through the air
supply/exhaust blowers 51a, 51b and the air supply ducts 6a, 6b. In
this embodiment, the opening degrees of the air return regulation
mechanisms 57a, 57b may be adjusted to control the amount of
outdoor air (OA) taken in.
[0133] <Refrigerant Exhaust Operation>
[0134] During the normal operation described above, when
refrigerant leaks in the usage-side air-conditioning apparatuses
3a, 3b, the leaked refrigerant is supplied to the air-conditioned
spaces S1, S2, and there is a risk of ignition accidents (when the
refrigerant is slightly flammable or flammable) or poisoning
accidents (when the refrigerant is toxic) occurring. In view of
this, when the refrigerant leakage detection devices 48a, 48b
detect refrigerant, a refrigerant exhaust operation is performed to
exhaust refrigerant together with the air in the casings 31a, 31b
out of the air-conditioned spaces S1, S2, by means of the air
supply/exhaust mechanisms. In this embodiment, the refrigerant
exhaust operation is performed by operating the air supply/exhaust
blowers 51a, 51b configuring the air supply/exhaust mechanisms in
the air exhaust state.
[0135] For example, supposing a case in which refrigerant has
leaked in the usage-side air-conditioning apparatus 3b (i.e., the
refrigerant leakage detection device 48b has detected refrigerant),
the air supply/exhaust blower 51b is operated in the air exhaust
state in the usage-side air-conditioning apparatus 3b as shown in
FIG. 8. Specifically, the air supply prevention mechanism 54b and
the intake prevention mechanism 56b are closed, the bypass
opening/closing mechanism 55b is opened, and the air supply/exhaust
blower 51b is operated. The leaked refrigerant, along with the air
in the casing 31b, is thereby passed through the bypass passage 53b
and exhausted to the intake duct 5 (5b). In this embodiment, when
the air supply/exhaust blower 51b is operated in the air exhaust
state, room air (RA) is taken into the casing 31b from the
air-conditioned space S2, and this room air (RA) is therefore
exhausted to the intake duct 5 (5b) along with the leaked
refrigerant. At this time, outdoor air (OA) is taken into the
casing 31b along with room air (RA), from outside the
air-conditioned space S2 through the air exhaust duct 8 (8b). In
the heat-source-side air-conditioning apparatus 2, refrigerant is
prevented from being supplied from the heat-source-side
air-conditioning apparatus 2 to the usage-side air-conditioning
apparatus 3b, for example, due to the compressor 21 being stopped.
In the usage-side air-conditioning apparatus 3a, in which
refrigerant is not leaking, the refrigerant that leaked in the
usage-side air-conditioning apparatus 3b is prevented from flowing
back to the casing 31a through the intake duct 5 (5a) by closing
the air return regulation mechanism 57a.
[0136] (3) Characteristics
[0137] The usage-side air-conditioning apparatuses 3a, 3b of the
present embodiment and the air-conditioning apparatus 1 provided
with the same have characteristics such as the following.
[0138] In this embodiment, as described above, in the usage-side
air-conditioning apparatuses 3a, 3b having the ventilating
air-condition function and the air-conditioning apparatus 1
provided with the same, when the refrigerant leakage detection
devices 48a, 48b detect refrigerant, the refrigerant exhaust
operation is performed by the air supply/exhaust mechanisms to
exhaust the refrigerant along with the air in the casings 31a, 31b
out of the air-conditioned spaces S1, S2. Particularly, in this
embodiment, the refrigerant exhaust operation is performed by
operating the air supply/exhaust blowers 51a, 51b in the air
exhaust state. Additionally, in this embodiment, the
air-conditioning apparatus 1 is configured by connecting the
heat-source-side air-conditioning apparatus 2 and the plurality
(two in this embodiment) of usage-side air-conditioning apparatuses
3a, 3b.
[0139] In this embodiment, when refrigerant leaks, it is thereby
possible to ensure that the leaked refrigerant is quickly exhausted
and not supplied to the air-conditioned spaces S1, S2, using the
air supply/exhaust mechanisms (in this embodiment, by operating the
air supply/exhaust blowers 51a, 51b in the air exhaust state).
Additionally, in this embodiment, when refrigerant has leaked in
any of the plurality of usage-side air-conditioning apparatuses 3a,
3b, it is possible to ensure that the leaked refrigerant is quickly
exhausted using the air supply/exhaust mechanism of the usage-side
air-conditioning apparatus 3a or 3b in which the refrigerant has
leaked, and that the refrigerant is not supplied to the
air-conditioned space S1 or S2 that is being air-conditioned by the
usage-side air-conditioning apparatus 3a or 3b in which the
refrigerant has leaked.
[0140] When the refrigerant is slightly flammable or flammable, the
occurrence of ignition accidents in the air-conditioned spaces S1,
S2 can be suppressed. When the refrigerant is toxic, the occurrence
of poisoning accidents in the air-conditioned spaces S1, S2 can be
suppressed. The occurrence of oxygen deficiency accidents in the
air-conditioned spaces S1, S2 can be suppressed even when the
refrigerant is not slightly flammable, flammable, or toxic.
[0141] This embodiment also has the characteristics <B> and
<C> of the first embodiment.
[0142] (4) Modifications
[0143] In the above-described usage-side air-conditioning
apparatuses 3a, 3b and the air-conditioning apparatus 1 provided
with the same (see FIGS. 6 to 8), the joints 13a, 13b, 14a, 14b
connecting the usage-side heat exchangers 33a, 33b to the
refrigerant interconnection pipes are provided inside the casings
31a, 31b, but there are also cases in which the joints 13a, 13b,
14a, 14b are provided outside of the casings 31a, 31b, similar to
the usage-side air-conditioning apparatuses 3a, 3b of the first
embodiment (FIG. 4). In these cases, when refrigerant leaks from
the joints 13a, 13b, 14a, 14b, the leakage occurs in the usage-side
installation spaces S3, S4 in which the casings 31a, 31b of the
usage-side air-conditioning apparatuses 3a, 3b are installed.
[0144] In view of this, in the above-described usage-side
air-conditioning apparatuses 3a, 3b and the air-conditioning
apparatus 1 provided with the same (see FIGS. 6 to 8), the
usage-side air-conditioning apparatuses 3a, 3b, similar to the
usage-side air-conditioning apparatuses 3a, 3b according to the
modification of the first embodiment, are provided with
inside-outside communication mechanisms 47a, 47b, which are capable
of switching between an inside-outside communication state of
allowing the usage-side installation spaces S3, S4 and the
interiors of the casings 31a, 31b to communicate, and an
inside-outside non-communication state of not allowing the
usage-side installation spaces S3, S4 and the interiors of the
casings 31a, 31b to communicate, the refrigerant exhaust operation
being performed by putting the inside-outside communication
mechanisms 47a, 47b in the inside-outside communication state.
[0145] Additionally, in the above-described usage-side
air-conditioning apparatuses 3a, 3b and the air-conditioning
apparatus 1 provided with the same (see FIGS. 6 to 8), the intake
duct 5 (5a, 5b) is used to exhaust leaked liquid refrigerant during
the refrigerant exhaust operation, but when a separate duct is
connected to the casings 31a, 31b, this separate duct may be used
for leaked refrigerant during the refrigerant exhaust operation. In
this case, outdoor air (OA) may continue to be taken into the
casings 31a, 31b through the intake duct 5 (5a, 5b) during the
refrigerant exhaust operation as well.
Third Embodiment
[0146] (1) Configuration
[0147] FIG. 9 is an overall configuration diagram of usage-side
air-conditioning apparatuses 3a, 3b according to a third embodiment
of the present invention, and an air-conditioning apparatus 1
provided with the same. FIG. 10 is a control block diagram of the
air-conditioning apparatus 1 in the third embodiment.
[0148] <Overall>
[0149] The air-conditioning apparatus 1, which is an
air-conditioning ventilation system having a ventilating
air-condition function for ventilating and air-conditioning the
interior of a room, mainly has a heat-source-side air-conditioning
apparatus 2, and a plurality (two in this embodiment) of usage-side
air-conditioning apparatuses 3a, 3b.
[0150] The air-conditioning apparatus 1 has a refrigerant circuit
10 through which refrigerant circulates. The refrigerant circuit 10
is configured by connecting the heat-source-side air-conditioning
apparatus 2 to the usage-side air-conditioning apparatuses 3a, 3b.
In this embodiment, the heat-source-side air-conditioning apparatus
2 is installed in a location such as on the roof of a building, and
the usage-side air-conditioning apparatuses 3a, 3b are installed in
usage-side installation spaces (in this embodiment, usage-side
installation spaces S3, S4), such as a machine room of the building
or a space above the ceiling, in correspondence with
air-conditioned spaces (in this embodiment, air-conditioned spaces
S1, S2) that are ventilated and air-conditioned. The
heat-source-side air-conditioning apparatus 2 and the usage-side
air-conditioning apparatuses 3a, 3b are connected via refrigerant
interconnection pipes 11, 12, thereby configuring the refrigerant
circuit 10. The refrigerant sealed within the refrigerant circuit
10 is a slightly flammable refrigerant such as R32, a flammable
refrigerant such as propane, or a toxic refrigerant such as
ammonia.
[0151] The air-conditioning apparatus 1 has a plurality of air
ducts. In this embodiment, the air-conditioning apparatus 1 has an
intake duct 5 for taking outdoor air (OA) into the usage-side
air-conditioning apparatuses 3a, 3b from outside the
air-conditioned spaces S1, S2, air supply ducts 6a, 6b for
supplying supply air (SA) from the usage-side air-conditioning
apparatuses 3a, 3b to the air-conditioned spaces S1, S2, and
outtake ducts 7a, 7b for taking room air (RA) from the
air-conditioned spaces S1, S2 into the corresponding usage-side
air-conditioning apparatuses 3a, 3b, whereby air can be exchanged
between the air-conditioned spaces S1, S2 and/or the outsides of
the air-conditioned spaces S1, S2 and the usage-side
air-conditioning apparatuses 3a, 3b. Also connected to the
air-conditioned spaces S1, S2 is an air exhaust duct 8 for
exhausting exhaust air (EA) out of the air-conditioned spaces S1,
S2. The intake duct 5 has intake branch ducts 5a, 5b that branch
corresponding to the usage-side air-conditioning apparatuses 3a,
3b, and the air exhaust duct 8 has air exhaust branch ducts 8a, 8b
that branch corresponding to the air-conditioned spaces S1, S2.
[0152] <Heat-Source-Side Air-Conditioning Apparatus>
[0153] The heat-source-side air-conditioning apparatus 2, as
described above, is connected to the usage-side air-conditioning
apparatuses 3a, 3b via the refrigerant interconnection pipes 11,
12, configuring part of the refrigerant circuit 10. The
configuration of the heat-source-side air-conditioning apparatus 2
according to the present embodiment is similar to the configuration
of the heat-source-side air-conditioning apparatus 2 of the first
embodiment described above (see FIG. 1), and is therefore not
described here.
[0154] <Usage-Side Air-Conditioning Apparatuses>
[0155] The usage-side air-conditioning apparatuses 3a, 3b, as
described above, are connected to the heat-source-side
air-conditioning apparatus 2 via the refrigerant interconnection
pipes 11, 12, configuring part of the refrigerant circuit 10.
Additionally, the usage-side air-conditioning apparatuses 3a, 3b,
as described above, are designed so as to be able to exchange air
with the air-conditioned spaces S1, S2 and/or the outsides of the
air-conditioned spaces S1, S2 via the air ducts 5 (5a, 5b), 6a, 6b,
7a, 7b. In the following description, the configuration of the
usage-side air-conditioning apparatus 3a is described, and
description of the configuration of the usage-side air-conditioning
apparatus 3b, in which the additional letter "a" is replaced by "b"
for each component, is omitted.
[0156] The usage-side air-conditioning apparatus 3a mainly has a
casing 31a, a usage-side expansion mechanism 32a, a usage-side heat
exchanger 33a, a second air supply blower 61a, a second air exhaust
blower 63a, and a refrigerant leakage detection device 48a.
[0157] The casing 31a is installed in the usage-side installation
space S3, and various ducts 5a, 6a, 7a are connected to the casing
31a. An air supply passage 42a to accommodate the usage-side heat
exchanger 33a and the like is formed in the casing 31a.
[0158] The usage-side expansion mechanism 32a is an electric
expansion valve that can, by performing opening degree control,
vary the flow rate of the refrigerant flowing through the
usage-side heat exchanger 33a. The usage-side expansion mechanism
32a is provided inside the casing 31a (inside the air supply
passage 42a in this embodiment). One end of the usage-side
expansion mechanism 32a is connected to a liquid side of the
usage-side expansion mechanism 32a, and another end of the
usage-side expansion mechanism 32a is connected to the liquid
refrigerant interconnection pipe 11 via a joint 13a. The joint 13a
is a pipe joint to connect the usage-side heat exchanger 33a to the
refrigerant interconnection pipes 11, 12, and in this embodiment,
is provided inside the casing 31a (inside the air supply passage
42a in this embodiment).
[0159] The usage-side heat exchanger 33a is a heat exchanger to
cool or heat the air (RA and/or OA) in the casing 31a by means of
the refrigerant supplied from the heat-source-side air-conditioning
apparatus 2. The usage-side heat exchanger 33a is provided inside
the casing 31a (inside the air supply passage 42a in this
embodiment). The usage-side heat exchanger 33a is connected to the
heat-source-side air-conditioning apparatus 2 via the refrigerant
interconnection pipes 11, 12. A liquid side of the usage-side heat
exchanger 33a is connected to the liquid refrigerant
interconnection pipe 11 via the usage-side expansion mechanism 32a
and the joint 13a, and a gas side of the usage-side heat exchanger
33a is connected to the gas refrigerant interconnection pipe 12 via
a joint 14a. The joint 14a is a pipe joint to connect the
usage-side heat exchanger 33a to the gas refrigerant
interconnection pipe 12, and in this embodiment, is provided inside
the casing 31a (inside the air supply passage 42a in this
embodiment).
[0160] The second air supply blower 61a is a fan provided to be
capable of taking room air (RA) in from the air-conditioned space
S1, taking outdoor air (OA) in from outside the air-conditioned
space S1, and supplying supply air (SA) to the air-conditioned
space S1. The second air supply blower 61a is provided inside the
air supply passage 42a, and an outlet of this blower is connected
to the air supply duct 6a. The second air supply blower 61a is
designed to be driven by a second air supply blower motor 62a.
[0161] The second air exhaust blower 63a is a fan provided so as to
be able to exhaust the exhaust air (EA) out of the air-conditioned
space S1. The second air exhaust blower 63a is provided inside the
air supply passage 42a, and an outlet of this blower is connected
to an inlet for outdoor air (OA) of the casing 31a. The second air
exhaust blower 63a is designed to be driven by a second air exhaust
blower motor 64a. Additionally, an air exhaust outlet communication
mechanism 65a, which is composed of a communication path to allow
communication between the air supply passage 42a and the outlet of
the second air exhaust blower 63a and an air damper placed in this
communication path, is provided to the outlet of the second air
exhaust blower 63a. The air exhaust outlet communication mechanism
65a is capable of switching between an outside air intake state of
allowing the inlet for outdoor air (OA) of the casing 31a to
communicate with the air supply passage 42a and enabling outdoor
air (OA) to be taken in from outside the air-conditioned space S1
by opening the air damper, and an air exhaust state of allowing the
outlet of the second air exhaust blower 63a to communicate with the
inlet for outdoor air (OA) of the casing 31a and enabling exhaust
air (EA) to be exhausted out of the air-conditioned space S1 by
closing the air damper. Additionally, an air return regulation
mechanism 66a composed of an air damper is provided to the inlet
for outdoor air (OA) of the casing 31a. The air return regulation
mechanism 66a may be provided to the intake branch duct 5a rather
than the inlet for outdoor air (OA) of the casing 31a. Thus, by
operating while the second air exhaust blower 63a is stopped and
the air exhaust outlet communication mechanism 65a is in the
outside air intake state, the second air supply blower 61a is able
to take room air (RA) in from the air-conditioned space S1, take
outdoor air (OA) in from outside the air-conditioned space S1, and
supply the air-conditioned space S1 with supply air (SA).
Additionally, the second air exhaust blower 63a is able to exhaust
the exhaust air (EA) out of the air-conditioned space S1 by
operating with the air exhaust outlet communication mechanism 65a
in the air exhaust state.
[0162] The above-described air passage 42a, mechanisms 65a, 66a,
and blowers 61a, 63a, when connected with the air ducts 5 (5a), 6a,
6b, 7a, 7b, configure an air supply/exhaust mechanism of the
usage-side air-conditioning apparatus 3a to take room air (RA) into
the casing 31a from the air-conditioned space S1, take outdoor air
(OA) into the casing 31a from outside the air-conditioned space S1,
supply the air inside the casing 31a as supply air (SA) to the
air-conditioned space S1, and exhaust the air inside the casing 31a
as exhaust air (EA) out of the air-conditioned space S1.
[0163] The refrigerant leakage detection device 48a is a device to
detect refrigerant. The refrigerant leakage detection device 48a is
provided inside the casing 31a. In this embodiment, the refrigerant
leakage detection device 48a is provided inside the air supply
passage 42a in which the usage-side heat exchanger 33a (in this
embodiment, the joints 13a, 14a and/or the usage-side expansion
mechanism 32a) is placed. Furthermore, in this embodiment, the
refrigerant leakage detection device 48a is provided either to a
lower part (when the refrigerant is denser than air) of the casing
31a (in this embodiment, the air supply passage 42a) or an upper
part (when the refrigerant is less dense than air) of the casing
31a (in this embodiment, the air supply passage 42a). FIG. 9 shows
a case in which the refrigerant leakage detection device 48a is
provided to the lower part of the casing 31a.
[0164] <Control Device>
[0165] The air-conditioning apparatus 1 has a control device 9 to
perform operation control on the heat-source-side air-conditioning
apparatus 2 and the usage-side air-conditioning apparatuses 3a, 3b,
etc. The control device 9 mainly has a heat-source-side control
device 92 to control the actions of the components (compressor,
etc.) configuring the heat-source-side air-conditioning apparatus
2, and usage-side control devices 93a, 93b to control the actions
of the components (fans, refrigerant leakage detection devices,
etc.) configuring the usage-side air-conditioning apparatuses 3a,
3b. The heat-source-side control device 92, which is provided to
the heat-source-side air-conditioning apparatus 2, has a
microcomputer and/or a memory, etc. for performing control on the
heat-source-side air-conditioning apparatus 2. The usage-side
control devices 93a, 93b, which are provided to the usage-side
air-conditioning apparatuses 3a, 3b, have microcomputers and/or
memories, etc. for performing control on the usage-side
air-conditioning apparatuses 3a, 3b. The heat-source-side control
device 92 and the usage-side control devices 93a, 93b are connected
so as to be capable of exchanging, for example, control signals via
a transmission line, and the control device 9 of the
air-conditioning apparatus 1 is thereby configured. In this
embodiment, the control devices 92, 93a, 93b are connected via a
transmission line, but are not limited to being connected in this
manner and may be connected wirelessly or by another connection
method.
[0166] (2) Actions
[0167] In the air-conditioning apparatus 1 having the configuration
described above, the following operations are performed. Operation
controls of the air-conditioning apparatus 1 described below are
performed by the control device 9.
[0168] <Normal Operation>
[0169] In normal operation, an operation is performed such that
outdoor air (OA) is taken into the casings 31a, 31b from outside
the air-conditioned spaces S1, S2, room air (RA) is taken into the
casings 31a, 31b from the air-conditioned spaces S1, S2, and the
air is cooled or heated in the usage-side heat exchangers 33a, 33b
and then supplied as supply air (SA) to the air-conditioned spaces
S1, S2, as shown in FIG. 9. In this embodiment, exhaust air (EA) is
exhausted out of the air-conditioned spaces S1, S2 through the air
exhaust duct 8 (8a, 8b) connected to the air-conditioned spaces S1,
S2. Specifically, operation control such as the following is
performed on the components of the air-conditioning apparatus
1.
[0170] When air is supplied as supply air (SA) to the
air-conditioned spaces S1, S2 after being cooled in the usage-side
heat exchangers 33a, 33b, in the heat-source-side air-conditioning
apparatus 2, the switching mechanism 23 is switched to the
air-cooling operation state (the state shown by the solid lines of
the switching mechanism 23 in FIG. 9), and the compressor 21 and
the heat-source-side fan 25 are driven. When air is supplied as
supply air (SA) to the air-conditioned spaces S1, S2 after being
heated in the usage-side heat exchangers 33a, 33b, in the
heat-source-side air-conditioning apparatus 2, the switching
mechanism 23 is switched to the air-warming operation state (the
state shown by the dashed lines of the switching mechanism 23 in
FIG. 9), and the compressor 21 and the heat-source-side fan 25 are
driven. In this embodiment, the actions of the components of the
refrigerant circuit 10, etc. are the same as the actions of the
components of the refrigerant circuit 10 etc. of the first
embodiment and are therefore not described here.
[0171] In the usage-side air-conditioning apparatuses 3a, 3b at
this time, the second air exhaust blowers 63a, 63b are stopped, the
air exhaust outlet communication mechanisms 65a, 65b and the air
return regulation mechanisms 66a, 66b are opened, and the second
air supply blowers 61a, 61b are driven. Specifically, the second
air supply blowers 61a, 61b are operated in the outside air intake
state. Due to these actions, outdoor air (OA) is taken into the air
supply passages 42a, 42b of the casings 31a, 31b from outside the
air-conditioned spaces S1, S2 through the intake duct 5 (5a, 5b),
and room air (RA) is taken into the air supply passages 42a, 42b of
the casings 31a, 31b from the air-conditioned spaces S1, S2 through
the outtake ducts 7a, 7b. The outdoor air (OA) and the room air
(RA) taken into the casings 31a, 31b is cooled or heated in the
usage-side heat exchangers 33a, 33b by refrigerant supplied from
the heat-source-side air-conditioning apparatus 2 through the
liquid refrigerant interconnection pipe 11. Having been cooled or
heated in the usage-side heat exchangers 33a, 33b, the outdoor air
(OA) or the outdoor air (OA) including room air (RA) is supplied as
supply air (SA) to the air-conditioned spaces S1, S2 through the
second air supply blowers 61a, 61b and the air supply ducts 6a, 6b.
In this embodiment, the opening degrees of the air return
regulation mechanisms 66a, 66b may be adjusted to control the
amount of outdoor air (OA) taken in.
[0172] <Refrigerant Exhaust Operation>
[0173] During the normal operation described above, when
refrigerant leaks in the usage-side air-conditioning apparatuses
3a, 3b, the leaked refrigerant is supplied to the air-conditioned
spaces S1, S2, and there is a risk of ignition accidents (when the
refrigerant is slightly flammable or flammable) or poisoning
accidents (when the refrigerant is toxic) occurring. In view of
this, when the refrigerant leakage detection devices 48a, 48b
detect refrigerant, a refrigerant exhaust operation is performed to
exhaust refrigerant together with the air in the casings 31a, 31b
out of the air-conditioned spaces S1, S2, by means of the air
supply/exhaust mechanisms. In this embodiment, the refrigerant
exhaust operation is performed by operating the second air exhaust
blowers 63a, 63b configuring the air supply/exhaust mechanisms in
the air exhaust state.
[0174] For example, supposing a case in which refrigerant has
leaked in the usage-side air-conditioning apparatus 3b (i.e., the
refrigerant leakage detection device 48b has detected refrigerant),
the second air exhaust blower 63b is operated in the air exhaust
state in the usage-side air-conditioning apparatus 3b as shown in
FIG. 11. Specifically, the air exhaust outlet communication
mechanism 65a is closed and the second air exhaust blower 63b is
operated. The leaked refrigerant, along with the air in the casing
31b, is thereby exhausted to the intake duct 5 (5b). At this time,
outdoor air (OA) is taken into the casing 31b along with room air
(RA), from outside the air-conditioned space S2 through the air
exhaust duct 8 (8b). The second air supply blower 61b is stopped
and leaked refrigerant is prevented from being supplied to the
air-conditioned space S2. In this embodiment, when the second air
exhaust blower 63b is operated, room air (RA) is taken into the
casing 31b from the air-conditioned space S2, and this room air
(RA) is exhausted along with the leaked refrigerant to the intake
duct 5 (5b). In the heat-source-side air-conditioning apparatus 2,
refrigerant is prevented from being supplied from the
heat-source-side air-conditioning apparatus 2 to the usage-side
air-conditioning apparatus 3b, for example, due to the compressor
21 being stopped. In the usage-side air-conditioning apparatus 3a,
in which refrigerant is not leaking, the refrigerant that leaked in
the usage-side air-conditioning apparatus 3b is prevented from
flowing back to the casing 31a through the intake duct 5 (5a) by
closing the air return regulation mechanism 66a.
[0175] (3) Characteristics
[0176] The usage-side air-conditioning apparatuses 3a, 3b of the
present embodiment and the air-conditioning apparatus 1 provided
with the same have characteristics such as the following.
[0177] In this embodiment, as described above, in the usage-side
air-conditioning apparatuses 3a, 3b having the ventilating
air-condition function and the air-conditioning apparatus 1
provided with the same, when the refrigerant leakage detection
devices 48a, 48b detect refrigerant, the refrigerant exhaust
operation is performed by the air supply/exhaust mechanisms to
exhaust the refrigerant along with the air in the casings 31a, 31b
out of the air-conditioned spaces S1, S2. Particularly, in this
embodiment, the refrigerant exhaust operation is performed by
operating the second air exhaust blowers 63a, 63b. Additionally, in
this embodiment, the air-conditioning apparatus 1 is configured by
connecting the heat-source-side air-conditioning apparatus 2 and
the plurality (two in this embodiment) of usage-side
air-conditioning apparatuses 3a, 3b.
[0178] In this embodiment, when refrigerant leaks, it is thereby
possible to ensure that the leaked refrigerant is quickly exhausted
and not supplied to the air-conditioned spaces S1, S2, using the
air supply/exhaust mechanisms (in this embodiment, by operating the
second air exhaust blowers 63a, 63b). Additionally, in this
embodiment, when refrigerant has leaked in any of the plurality of
usage-side air-conditioning apparatuses 3a, 3b, it is possible to
ensure that the leaked refrigerant is quickly exhausted using the
air supply/exhaust mechanism of the usage-side air-conditioning
apparatus 3a or 3b in which the refrigerant has leaked, and that
the refrigerant is not supplied to the air-conditioned space S1 or
S2 that is being air-conditioned by the usage-side air-conditioning
apparatus 3a or 3b in which the refrigerant has leaked.
[0179] When the refrigerant is slightly flammable or flammable, the
occurrence of ignition accidents in the air-conditioned spaces S1,
S2 can be suppressed. When the refrigerant is toxic, the occurrence
of poisoning accidents in the air-conditioned spaces S1, S2 can be
suppressed. The occurrence of oxygen deficiency accidents in the
air-conditioned spaces S1, S2 can be suppressed even when the
refrigerant is not slightly flammable, flammable, or toxic.
[0180] This embodiment also has the characteristics <B> and
<C> of the first embodiment.
[0181] (4) Modifications
[0182] In the above-described usage-side air-conditioning
apparatuses 3a, 3b and the air-conditioning apparatus 1 provided
with the same (see FIGS. 9 to 11), the joints 13a, 13b, 14a, 14b
connecting the usage-side heat exchangers 33a, 33b to the
refrigerant interconnection pipes are provided inside the casings
31a, 31b, but there are also cases in which the joints 13a, 13b,
14a, 14b are provided outside of the casings 31a, 31b, similar to
the usage-side air-conditioning apparatuses 3a, 3b of the first
embodiment (FIG. 4). In these cases, when refrigerant leaks from
the joints 13a, 13b, 14a, 14b, the leakage occurs in the usage-side
installation spaces S3, S4 in which the casings 31a, 31b of the
usage-side air-conditioning apparatuses 3a, 3b are installed.
[0183] In view of this, in the above-described usage-side
air-conditioning apparatuses 3a, 3b and the air-conditioning
apparatus 1 provided with the same (see FIGS. 9 to 11), the
usage-side air-conditioning apparatuses 3a, 3b, similar to the
usage-side air-conditioning apparatuses 3a, 3b according to the
modification of the first embodiment, are provided with
inside-outside communication mechanisms 47a, 47b, which are capable
of switching between an inside-outside communication state of
allowing the usage-side installation spaces S3, S4 and the
interiors of the casings 31a, 31b to communicate, and an
inside-outside non-communication state of not allowing the
usage-side installation spaces S3, S4 and the interiors of the
casings 31a, 31b to communicate, the refrigerant exhaust operation
being performed by putting the inside-outside communication
mechanisms 47a, 47b in the inside-outside communication state.
Fourth Embodiment
[0184] (1) Configuration
[0185] FIG. 12 is an overall configuration diagram of usage-side
air-conditioning apparatuses 3a, 3b according to a fourth
embodiment of the present invention, and an air-conditioning
apparatus 1 provided with the same. FIG. 13 is a control block
diagram of the air-conditioning apparatus 1 in the fourth
embodiment.
[0186] <Overall>
[0187] The air-conditioning apparatus 1, which is an
air-conditioning ventilation system having a ventilating
air-condition function for ventilating and air-conditioning the
interior of a room, mainly has a heat-source-side air-conditioning
apparatus 2, and a plurality (two in this embodiment) of usage-side
air-conditioning apparatuses 3a, 3b.
[0188] The air-conditioning apparatus 1 has a refrigerant circuit
10 through which refrigerant circulates. The refrigerant circuit 10
is configured by connecting the heat-source-side air-conditioning
apparatus 2 to the usage-side air-conditioning apparatuses 3a, 3b.
In this embodiment, the heat-source-side air-conditioning apparatus
2 is installed in a location such as on the roof of a building, and
the usage-side air-conditioning apparatuses 3a, 3b are installed in
usage-side installation spaces (in this embodiment, usage-side
installation spaces S3, S4), such as a machine room of the building
or a space above the ceiling, in correspondence with
air-conditioned spaces (in this embodiment, air-conditioned spaces
S1, S2) that are ventilated and air-conditioned. The
heat-source-side air-conditioning apparatus 2 and the usage-side
air-conditioning apparatuses 3a, 3b are connected via refrigerant
interconnection pipes 11, 12, thereby configuring the refrigerant
circuit 10. The refrigerant sealed within the refrigerant circuit
10 is a slightly flammable refrigerant such as R32, a flammable
refrigerant such as propane, or a toxic refrigerant such as
ammonia.
[0189] The air-conditioning apparatus 1 has a plurality of air
ducts. In this embodiment, the air-conditioning apparatus 1 has an
intake duct 5 for taking outdoor air (OA) into the usage-side
air-conditioning apparatuses 3a, 3b from outside the
air-conditioned spaces S1, S2, air supply ducts 6a, 6b for
supplying supply air (SA) from the usage-side air-conditioning
apparatuses 3a, 3b to the air-conditioned spaces S1, S2, outtake
ducts 7a, 7b for taking room air (RA) from the air-conditioned
spaces S1, S2 into the corresponding usage-side air-conditioning
apparatuses 3a, 3b, and an air exhaust duct 8 for exhausting
exhaust air (EA) from the usage-side air-conditioning apparatuses
3a, 3b out of the air-conditioned spaces S1, S2 whereby air can be
exchanged between the air-conditioned spaces S1, S2 and/or the
outsides of the air-conditioned spaces S1, S2 and the usage-side
air-conditioning apparatuses 3a, 3b. The intake duct 5 has intake
branch ducts 5a, 5b that branch corresponding to the usage-side
air-conditioning apparatuses 3a, 3b, and the air exhaust duct 8 has
air exhaust branch ducts 8a, 8b that branch corresponding to the
usage-side air-conditioning apparatuses 3a, 3b.
[0190] <Heat-Source-Side Air-Conditioning Apparatus>
[0191] The heat-source-side air-conditioning apparatus 2, as
described above, is connected to the usage-side air-conditioning
apparatuses 3a, 3b via the refrigerant interconnection pipes 11,
12, configuring part of the refrigerant circuit 10. The
configuration of the heat-source-side air-conditioning apparatus 2
according to the present embodiment is similar to the configuration
of the heat-source-side air-conditioning apparatus 2 of the first
embodiment described above (see FIG. 1), and is therefore not
described here.
[0192] <Usage-Side Air-Conditioning Apparatuses>
[0193] The usage-side air-conditioning apparatuses 3a, 3b, as
described above, are connected to the heat-source-side
air-conditioning apparatus 2 via the refrigerant interconnection
pipes 11, 12, configuring part of the refrigerant circuit 10.
Additionally, the usage-side air-conditioning apparatuses 3a, 3b,
as described above, are designed so as to be able to exchange air
with the air-conditioned spaces S1, S2 and/or the outsides of the
air-conditioned spaces S1, S2 via the air ducts 5 (5a, 5b), 6a, 6b,
7a, 7b, 8 (8a, 8b). In the following description, the configuration
of the usage-side air-conditioning apparatus 3a is described, and
description of the configuration of the usage-side air-conditioning
apparatus 3b, in which the additional letter "a" is replaced by "b"
for each component, is omitted.
[0194] The usage-side air-conditioning apparatus 3a mainly has a
casing 31a, a usage-side expansion mechanism 32a, a usage-side heat
exchanger 33a, a third air supply blower 71a, a third air exhaust
blower 73a, and a refrigerant leakage detection device 48a.
[0195] The casing 31a is installed in the usage-side installation
space S3, and various ducts 5a, 6a, 7a, 8a are connected to the
casing 31a. A space to accommodate the usage-side heat exchanger
33a and the like is formed in the casing 31a.
[0196] The usage-side expansion mechanism 32a is an electric
expansion valve that can, by performing opening degree control,
vary the flow rate of the refrigerant flowing through the
usage-side heat exchanger 33a. The usage-side expansion mechanism
32a is provided inside the casing 31a. One end of the usage-side
expansion mechanism 32a is connected to a liquid side of the
usage-side expansion mechanism 32a, and another end of the
usage-side expansion mechanism 32a is connected to the liquid
refrigerant interconnection pipe 11 via a joint 13a. The joint 13a
is a pipe joint to connect the usage-side heat exchanger 33a to the
refrigerant interconnection pipes 11, 12, and in this embodiment,
is provided inside the casing 31a.
[0197] The usage-side heat exchanger 33a is a heat exchanger to
cool or heat the air (RA and/or OA) in the casing 31a by means of
the refrigerant supplied from the heat-source-side air-conditioning
apparatus 2. The usage-side heat exchanger 33a is provided inside
the casing 31a. The usage-side heat exchanger 33a is connected to
the heat-source-side air-conditioning apparatus 2 via the
refrigerant interconnection pipes 11, 12. A liquid side of the
usage-side heat exchanger 33a is connected to the liquid
refrigerant interconnection pipe 11 via the usage-side expansion
mechanism 32a and the joint 13a, and a gas side of the usage-side
heat exchanger 33a is connected to the gas refrigerant
interconnection pipe 12 via a joint 14a. The joint 14a is a pipe
joint to connect the usage-side heat exchanger 33a to the gas
refrigerant interconnection pipe 12, and in this embodiment, is
provided inside the casing 31a. The space inside the casing 31a is
divided into an air supply passage 42a and an air exhaust passage
44a. The air supply passage 42a communicates with the intake duct 5
(5a) and the air supply duct 6a, and the air exhaust passage 44a
communicates with the outtake duct 7a and the air exhaust duct 8
(8a). The usage-side expansion mechanism 32a and the usage-side
heat exchanger 33a are provided inside the air supply passage 42a
within the space inside the casing 31a, and in this embodiment, the
joints 13a, 14a are also provided inside the air supply passage
42a. Therefore, the usage-side heat exchanger 33a is designed so as
to cool or heat the air inside the air supply passage 42a.
[0198] The third air supply blower 71a is a fan provided to be
capable of taking outdoor air (OA) in from outside the
air-conditioned space S1 and supplying supply air (SA) to the
air-conditioned space S1. The third air supply blower 71a is
provided inside the air supply passage 42a, and an outlet of this
blower is connected to the air supply duct 6a. The third air supply
blower 71a is designed to be driven by a third air supply blower
motor 72a.
[0199] The third air exhaust blower 73a is a fan provided so as to
be capable of taking room air (RA) in from the air-conditioned
space S1, returning some of the room air (RA) to the outdoor air
(OA) taken in by the third air supply blower 73a, and exhaust the
remnant of the room air (RA) as exhaust air (EA) out of the
air-conditioned space S1. The third air exhaust blower 73a is
provided inside the air exhaust passage 44a, and an outlet of this
blower is connected to the air exhaust duct 8 (8a). The third air
exhaust blower 73a is designed to be driven by a third air exhaust
blower motor 74a. Additionally, an air exhaust outlet communication
mechanism 75a, which is composed of a communication path to allow
communication between the air supply passage 42a and the outlet of
the third air exhaust blower 73a and an air damper placed in this
communication path, is provided to the outlet of the third air
exhaust blower 73a. The air exhaust outlet communication mechanism
75a is capable of switching between: a partial exhaust state of
allowing the outlet of the third air exhaust blower 73a to
communicate with the air supply passage 42a, returning some of the
room air (RA) to the outdoor air (OA) inside the air supply passage
42a, and exhausting the remnant of the room air (RA) as exhaust air
(EA) out of the air-conditioned space S1, by opening the air
damper; and a full exhaust state of not allowing the outlet of the
third air exhaust blower 73a to communicate with the air supply
passage 42a, and exhausting all of the room air (RA) as exhaust air
(EA) out of the air-conditioned space S1, by closing the air
damper. Additionally, an air supply/exhaust communication mechanism
76a, composed of a communication path to allow the air supply
passage 42a and the air exhaust passage 44a to communicate and an
air damper placed in this communication path, is provided to the
casing 31a. The air supply/exhaust communication mechanism 76a is
capable of switching between an air supply-exhaust communication
state of allowing the air supply passage 42a and the air exhaust
passage 44a to communicate by opening the air damper, and an air
supply-exhaust non-communication state of not allowing the air
supply passage 42a and the air exhaust passage 44a to communicate
by closing the air damper. An air return regulation mechanism 77a
composed of an air damper is provided to an outlet for exhaust air
(EA) of the casing 31a. The air return regulation mechanism 77a may
be provided to the air exhaust branch duct 8a rather than to the
outlet for exhaust air (EA) of the casing 31a.
[0200] The above-described air passages 42a, 44a, mechanisms 75a,
76a, 77a, and blowers 71a, 73a, when connected with the air ducts 5
(5a), 6a, 6b, 7a, 7b, 8 (8a), configure an air supply/exhaust
mechanism of the usage-side air-conditioning apparatus 3a to take
outdoor air (OA) in from outside the air-conditioned space S1,
supply the air-conditioned space S1 with supply air (SA), take room
air (RA) in from the air-conditioned space S1, return some of the
room air (RA) to the outdoor air (OA), and exhaust the remnant of
the room air (RA) as exhaust air (EA) out of the air-conditioned
space S1.
[0201] The refrigerant leakage detection device 48a is a device to
detect refrigerant. The refrigerant leakage detection device 48a is
provided inside the casing 31a. In this embodiment, the refrigerant
leakage detection device 48a is provided inside the air supply
passage 42a in which the usage-side heat exchanger 33a (in this
embodiment, the joints 13a, 14a and/or the usage-side expansion
mechanism 32a) is placed. Furthermore, in this embodiment, the
refrigerant leakage detection device 48a is provided either to a
lower part (when the refrigerant is denser than air) of the casing
31a (in this embodiment, the air supply passage 42a) or an upper
part (when the refrigerant is less dense than air) of the casing
31a (in this embodiment, the air supply passage 42a). FIG. 12 shows
a case in which the refrigerant leakage detection device 48a is
provided to the lower part of the casing 31a.
[0202] <Control Device>
[0203] The air-conditioning apparatus 1 has a control device 9 to
perform operation control on the heat-source-side air-conditioning
apparatus 2 and the usage-side air-conditioning apparatuses 3a, 3b
etc. The control device 9 mainly has a heat-source-side control
device 92 to control the actions of the components (compressor
etc.) configuring the heat-source-side air-conditioning apparatus
2, and usage-side control devices 93a, 93b to control the actions
of the components (fans, refrigerant leakage detection devices,
etc.) configuring the usage-side air-conditioning apparatuses 3a,
3b. The heat-source-side control device 92, which is provided to
the heat-source-side air-conditioning apparatus 2, has a
microcomputer and/or a memory etc. for performing control on the
heat-source-side air-conditioning apparatus 2. The usage-side
control devices 93a, 93b, which are provided to the usage-side
air-conditioning apparatuses 3a, 3b, have microcomputers and/or
memories etc. for performing control on the usage-side
air-conditioning apparatuses 3a, 3b. The heat-source-side control
device 92 and the usage-side control devices 93a, 93b are connected
so as to be capable of exchanging, for example, control signals via
a transmission line, and the control device 9 of the
air-conditioning apparatus 1 is thereby configured. In this
embodiment, the control devices 92, 93a, 93b are connected via a
transmission line, but are not limited to being connected in this
manner and may be connected wirelessly or by another connection
method.
[0204] (2) Actions
[0205] In the air-conditioning apparatus 1 having the configuration
described above, the following operations are performed. Operation
controls of the air-conditioning apparatus 1 described below are
performed by the control device 9.
[0206] <Normal Operation>
[0207] In normal operation, an operation is performed such that
outdoor air (OA) is taken into the casings 31a, 31b from outside
the air-conditioned spaces S1, S2, room air (RA) is taken into the
casings 31a, 31b from the air-conditioned spaces S1, S2 some of the
room air (RA) is returned to the outdoor air (OA), the returned air
(OA and some of RA) is cooled or heated in the usage-side heat
exchangers 33a, 33b and then supplied as supply air (SA) to the
air-conditioned spaces S1, S2, and the remnant of the room air (RA)
is exhausted as exhaust air (EA) out of the air-conditioned space
S1, as shown in FIG. 12. Specifically, operation control such as
the following is performed on the components of the
air-conditioning apparatus 1.
[0208] When air is supplied as supply air (SA) to the
air-conditioned spaces S1, S2 after being cooled in the usage-side
heat exchangers 33a, 33b, in the heat-source-side air-conditioning
apparatus 2, the switching mechanism 23 is switched to the
air-cooling operation state (the state shown by the solid lines of
the switching mechanism 23 in FIG. 12), and the compressor 21 and
the heat-source-side fan 25 are driven. When air is supplied as
supply air (SA) to the air-conditioned spaces S1, S2 after being
heated in the usage-side heat exchangers 33a, 33b, in the
heat-source-side air-conditioning apparatus 2, the switching
mechanism 23 is switched to the air-warming operation state (the
state shown by the dashed lines of the switching mechanism 23 in
FIG. 12), and the compressor 21 and the heat-source-side fan 25 are
driven. In this embodiment, the actions of the components of the
refrigerant circuit 10 etc. are the same as the actions of the
components of the refrigerant circuit 10, etc. of the first
embodiment and are therefore not described here.
[0209] In the usage-side air-conditioning apparatuses 3a, 3b at
this time, the air exhaust outlet communication mechanisms 75a, 75b
and the air return regulation mechanisms 77a, 77b are opened, the
air supply/exhaust communication mechanism 76a is closed, and the
third air supply blowers 71a, 71b and the third air exhaust blowers
73a, 73b are driven. Due to these actions, outdoor air (OA) is
taken into the air supply passages 42a, 42b of the casings 31a, 31b
from outside the air-conditioned spaces S1, S2 through the intake
duct 5 (5a, 5b), and room air (RA) is taken into the air exhaust
passages 44a, 44b of the casings 31a, 31b from the air-conditioned
spaces S1, S2 through the outtake ducts 7a, 7b. The room air (RA)
taken into the casings 31a, 31b is sent by the third air exhaust
blowers 73a, 73b to the outlets thereof. Some of the room air (RA)
sent to the outlets of the third air exhaust blowers 73a, 73b is
sent through the air exhaust outlet communication mechanisms 75a,
75b to the air supply passage 42a to merge with the outdoor air
(OA) in accordance with the opening degrees of the air dampers of
the air return regulation mechanisms 77a, 77b, and the remnant of
the room air (RA) is exhausted as exhaust air (EA) out of the
air-conditioned spaces S1, S2 through the air exhaust duct 8 (8a,
8b). With the merged room air (RA), the outdoor air (OA) is cooled
or heated in the usage-side heat exchangers 33a, 33b by refrigerant
supplied from the heat-source-side air-conditioning apparatus 2
through the liquid refrigerant interconnection pipe 11. Having been
cooled or heated in the usage-side heat exchangers 33a, 33b, the
outdoor air (OA) including room air (RA) is supplied as supply air
(SA) to the air-conditioned spaces S1, S2 through the third air
supply blowers 71a, 71b and the air supply ducts 6a, 6b.
[0210] <Refrigerant Exhaust Operation>
[0211] During the normal operation described above, when
refrigerant leaks in the usage-side air-conditioning apparatuses
3a, 3b, the leaked refrigerant is supplied to the air-conditioned
spaces S1, S2, and there is a risk of ignition accidents (when the
refrigerant is slightly flammable or flammable) or poisoning
accidents (when the refrigerant is toxic) occurring. In view of
this, when the refrigerant leakage detection devices 48a, 48b
detect refrigerant, a refrigerant exhaust operation is performed to
exhaust refrigerant together with the air in the casings 31a, 31b
out of the air-conditioned spaces S1, S2, by means of the air
supply/exhaust mechanisms. In this embodiment, the refrigerant
exhaust operation is performed by operating the third air exhaust
blowers 73a, 73b configuring the air supply/exhaust mechanisms.
[0212] For example, supposing a case in which refrigerant has
leaked in the usage-side air-conditioning apparatus 3b (i.e., the
refrigerant leakage detection device 48b has detected refrigerant),
the third air exhaust blower 73b is operated in the usage-side
air-conditioning apparatus 3b as shown in FIG. 14. Specifically,
the air exhaust outlet communication mechanism 75b is closed, the
air supply/exhaust communication mechanism 76b is opened, and the
third air exhaust blower 73b is operated. The leaked refrigerant,
along with the air in the casing 31b, is thereby exhausted to the
air exhaust duct 8 (8b) through the air supply passage 42b and the
air exhaust passage 44b. The third air supply blower 71b is stopped
and leaked refrigerant is prevented from being supplied to the
air-conditioned space S2. In this embodiment, when the third air
exhaust blower 73b is operated, room air (RA) is taken into the
casing 31b from the air-conditioned space S2, and this room air
(RA) is exhausted along with the leaked refrigerant to the air
exhaust duct 8 (8b). In the heat-source-side air-conditioning
apparatus 2, refrigerant refrigerant is prevented from being
supplied from the heat-source-side air-conditioning apparatus 2 to
the usage-side air-conditioning apparatus 3b, for example, due to
the compressor 21 being stopped. In the usage-side air-conditioning
apparatus 3a, in which refrigerant is not leaking, the refrigerant
that leaked in the usage-side air-conditioning apparatus 3b is
prevented from flowing back to the casing 31a through the air
exhaust duct 8 (8a) by closing the air return regulation mechanism
77a.
[0213] (3) Characteristics
[0214] The usage-side air-conditioning apparatuses 3a, 3b of the
present embodiment and the air-conditioning apparatus 1 provided
with the same have characteristics such as the following.
[0215] In this embodiment, as described above, in the usage-side
air-conditioning apparatuses 3a, 3b having the ventilating
air-condition function and the air-conditioning apparatus 1
provided with the same, when the refrigerant leakage detection
devices 48a, 48b detect refrigerant, the refrigerant exhaust
operation is performed by the air supply/exhaust mechanisms to
exhaust the refrigerant along with the air in the casings 31a, 31b
out of the air-conditioned spaces S1, S2. Particularly, in this
embodiment, the refrigerant exhaust operation is performed by
operating the third air exhaust blowers 73a, 73b. Additionally, in
this embodiment, the air-conditioning apparatus 1 is configured by
connecting the heat-source-side air-conditioning apparatus 2 and
the plurality (two in this embodiment) of usage-side
air-conditioning apparatuses 3a, 3b.
[0216] In this embodiment, when refrigerant leaks, it is thereby
possible to ensure that the leaked refrigerant is quickly exhausted
and not supplied to the air-conditioned spaces S1, S2, using the
air supply/exhaust mechanisms (in this embodiment, by operating the
third air exhaust blowers 73a, 73b). Additionally, in this
embodiment, when refrigerant has leaked in any of the plurality of
usage-side air-conditioning apparatuses 3a, 3b, it is possible to
ensure that the leaked refrigerant is quickly exhausted using the
air supply/exhaust mechanism of the usage-side air-conditioning
apparatus 3a or 3b in which the refrigerant has leaked, and that
the refrigerant is not supplied to the air-conditioned space S1 or
S2 that is being air-conditioned by the usage-side air-conditioning
apparatus 3a or 3b in which the refrigerant has leaked.
[0217] When the refrigerant is slightly flammable or flammable, the
occurrence of ignition accidents in the air-conditioned spaces S1,
S2 can be suppressed. When the refrigerant is toxic, the occurrence
of poisoning accidents in the air-conditioned spaces S1, S2 can be
suppressed. The occurrence of oxygen deficiency accidents in the
air-conditioned spaces S1, S2 can be suppressed even when the
refrigerant is not slightly flammable, flammable, or toxic.
[0218] This embodiment also has the characteristics <B> and
<C> of the first embodiment.
[0219] (4) Modifications
[0220] In the above-described usage-side air-conditioning
apparatuses 3a, 3b and the air-conditioning apparatus 1 provided
with the same (see FIGS. 12 to 14), the joints 13a, 13b, 14a, 14b
connecting the usage-side heat exchangers 33a, 33b to the
refrigerant interconnection pipes are provided inside the casings
31a, 31b, but there are also cases in which the joints 13a, 13b,
14a, 14b are provided outside of the casings 31a, 31b, similar to
the usage-side air-conditioning apparatuses 3a, 3b of the first
embodiment (FIG. 4). In these cases, when refrigerant leaks from
the joints 13a, 13b, 14a, 14b, the leakage occurs in the usage-side
installation spaces S3, S4 in which the casings 31a, 31b of the
usage-side air-conditioning apparatuses 3a, 3b are installed.
[0221] In view of this, in the above-described usage-side
air-conditioning apparatuses 3a, 3b and the air-conditioning
apparatus 1 provided with the same (see FIGS. 12 to 14), the
usage-side air-conditioning apparatuses 3a, 3b, similar to the
usage-side air-conditioning apparatuses 3a, 3b according to the
modification of the first embodiment, are provided with
inside-outside communication mechanisms 47a, 47b, which are capable
of switching between an inside-outside communication state of
allowing the usage-side installation spaces S3, S4 and the
interiors of the casings 31a, 31b to communicate, and an
inside-outside non-communication state of not allowing the
usage-side installation spaces S3, S4 and the interiors of the
casings 31a, 31b to communicate, the refrigerant exhaust operation
being performed by putting the inside-outside communication
mechanisms 47a, 47b in the inside-outside communication state.
INDUSTRIAL APPLICABILITY
[0222] The present invention is widely applicable to: usage-side
air-conditioning apparatuses that have usage-side heat exchangers
to cool or heat air inside casings by means of refrigerant supplied
from a heat-source-side air-conditioning apparatus, and air
supply/exhaust mechanisms to take air into the casings from
air-conditioned spaces or outside air-conditioned spaces and to
supply the air inside the casings to the air-conditioned spaces or
to the outsides of the air-conditioned spaces; and air-conditioning
apparatuses that are provided with such usage-side air-conditioning
apparatuses.
REFERENCE SIGNS LIST
[0223] 1 Air-conditioning apparatus [0224] 2 Heat-source-side
air-conditioning apparatus [0225] 3a, 3b Usage-side
air-conditioning apparatuses [0226] 11, 12 Refrigerant
interconnection pipes [0227] 13a, 13b, 14a, 14b Joints [0228] 31a,
31b Casings [0229] 33a, 33b Usage-side heat exchangers [0230] 35a,
35b First air supply blowers [0231] 37a, 37b First air exhaust
blowers [0232] 47a, 47b Inside-outside communication mechanisms
[0233] 48a, 48b, 49a, 49b Refrigerant leakage detection devices
[0234] 51a, 51b Air supply/exhaust blowers [0235] 61a, 61b Second
air supply blowers [0236] 63a, 63b Second air exhaust blowers
[0237] 71a, 71b Third air supply blowers [0238] 73a, 73b Third air
exhaust blowers
CITATION LIST
Patent Literature
[0239] Patent Literature 1: Japanese Laid-open Patent Publication
No. 2000-220877
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