U.S. patent application number 13/982503 was filed with the patent office on 2013-11-21 for refrigerating and air-conditioning apparatus.
This patent application is currently assigned to MITSUBISHI ELECTRIC CORPORATION. The applicant listed for this patent is Kenji Matsui. Invention is credited to Kenji Matsui.
Application Number | 20130305758 13/982503 |
Document ID | / |
Family ID | 46757417 |
Filed Date | 2013-11-21 |
United States Patent
Application |
20130305758 |
Kind Code |
A1 |
Matsui; Kenji |
November 21, 2013 |
REFRIGERATING AND AIR-CONDITIONING APPARATUS
Abstract
A refrigerating and air-conditioning apparatus that achieves
reduced limitations with respect to the communication of indoor
units and can identify which indoor unit is connected to each
branch port is obtained. Indoor units are made to operate on a
one-by-one basis, and it is identified which indoor unit is
connected to each branch port on the basis of the difference
between an inlet temperature and an outlet temperature at the
branch port at that time.
Inventors: |
Matsui; Kenji; (Tokyo,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Matsui; Kenji |
Tokyo |
|
JP |
|
|
Assignee: |
MITSUBISHI ELECTRIC
CORPORATION
Tokyo
JP
|
Family ID: |
46757417 |
Appl. No.: |
13/982503 |
Filed: |
March 1, 2011 |
PCT Filed: |
March 1, 2011 |
PCT NO: |
PCT/JP2011/001174 |
371 Date: |
July 30, 2013 |
Current U.S.
Class: |
62/129 |
Current CPC
Class: |
F25B 2313/02741
20130101; F25B 49/005 20130101; F25B 2313/0231 20130101; F25B
25/005 20130101; F25B 2313/0272 20130101; F25B 49/02 20130101; F25B
13/00 20130101; F25B 2313/0314 20130101 |
Class at
Publication: |
62/129 |
International
Class: |
F25B 49/02 20060101
F25B049/02 |
Claims
1. A refrigerating and air-conditioning apparatus comprising: a
refrigeration cycle that makes a refrigerant circulate therethrough
by connecting a compressor, a heat-source-side heat exchanger, at
least one expansion valve, and at least one intermediate heat
exchanger; and a heat-medium circuit that makes a heat medium
circulate therethrough by connecting at least one pump, a plurality
of use-side heat exchangers, and the intermediate heat exchanger,
wherein the at least one intermediate heat exchanger and the at
least one pump are accommodated in a relay unit, wherein the
plurality of use-side heat exchangers are accommodated in
respective indoor units, wherein each indoor unit includes an
indoor-unit controller that performs on-off control for operation
performed by the use-side heat exchanger for exchanging heat
between the heat medium and a thermal load, wherein the relay unit
includes a plurality of branch ports that are connected to the
plurality of use-side heat exchangers and make the heat medium
circulate to the use-side heat exchangers, outlet temperature
sensors that are provided for the respective branch ports and each
detect an outlet temperature of the heat medium flowing out of the
branch port to the corresponding use-side heat exchanger, inlet
temperature sensors that are provided for the respective branch
ports and each detect an inlet temperature of the heat medium
flowing into the branch port from the corresponding use-side heat
exchanger, and a relay-unit controller that is connected to the
indoor-unit controllers by a transmission line and controls
operation of each indoor-unit by transmitting an operation command
or a stop command thereto via the transmission line, and wherein
the relay-unit controller makes the indoor units operate on a
one-by-one basis and identifies which of the indoor units is
connected to each branch port on the basis of a difference between
the inlet temperature and the outlet temperature at the branch
port.
2. The refrigerating and air-conditioning apparatus of claim 1,
wherein, in a state where the heat medium heated or cooled by
performing a heating only operation mode, in which the heat medium
is heated by causing a high-temperature high-pressure refrigerant
discharged from the compressor to flow to the intermediate heat
exchanger, or a cooling only operation mode, in which the heat
medium is cooled by causing a low-temperature low-pressure
refrigerant to flow to the intermediate heat exchanger, circulates
to the plurality of use-side heat exchangers, the relay-unit
controller makes each indoor unit operate on a one-by-one basis,
acquires the inlet temperature and the outlet temperature at each
branch port, and identifies that the operating indoor unit is
connected to the branch port at which the difference between the
inlet temperature and the outlet temperature is larger than a
predetermined value.
3. The refrigerating and air-conditioning apparatus of claim 1,
wherein, in a state where the heat medium heated or cooled by
performing a heating only operation mode, in which the heat medium
is heated by causing a high-temperature high-pressure refrigerant
discharged from the compressor to flow to the intermediate heat
exchanger, or a cooling only operation mode, in which the heat
medium is cooled by causing a low-temperature low-pressure
refrigerant to flow to the intermediate heat exchanger, circulates
to the plurality of use-side heat exchangers, the relay-unit
controller makes each indoor unit operate on a one-by-one basis,
acquires the inlet temperature and the outlet temperature at each
branch port, and determines there is a setting error if at none of
the branch ports the difference between the inlet temperature and
the outlet temperature is larger than a predetermined value.
4. The refrigerating and air-conditioning apparatus of claim 1,
wherein the relay-unit controller transmits a binary signal
corresponding to the operation command and the stop command via the
transmission line, and wherein each indoor-unit controller performs
on-off control for the operation of the indoor unit in accordance
with the binary signal received via the transmission line.
5. The refrigerating and air-conditioning apparatus of claim 1,
wherein only a binary signal is transmitted via the transmission
line.
Description
TECHNICAL FIELD
[0001] The present invention relates to refrigerating and
air-conditioning apparatuses, and particularly, to a refrigerating
and air-conditioning apparatus equipped with a plurality of
use-side heat exchangers.
BACKGROUND ART
[0002] In the conventional art, for example, there has been
proposed a matter "detecting a first temperature of a heat
exchanger in each indoor unit when all of flow control valves in a
branch kit 30 are opened in a case where a refrigerant is supplied
to each outdoor-unit-side refrigerant-pipe connection port
connected to the branch kit 30; then detecting a second temperature
of each indoor heat exchanger when the flow control valves in the
branch kit are closed on a one-by-one basis; identifying an indoor
unit corresponding to a heat exchanger in which a predetermined
change in the second temperature with reference to the first
temperature is obtained as an indoor unit that is connected to the
refrigerant-pipe connection port corresponding to one of the closed
flow control valves, and setting a specific identification address
for the identified indoor unit." (for example, see Patent
Literature 1).
CITATION LIST
Patent Literature
[0003] Patent Literature 1: Japanese Unexamined Patent Application
Publication No. 9-229457 (Abstract)
SUMMARY OF INVENTION
Technical Problem
[0004] In a refrigerating and air-conditioning apparatus in the
related art that can simultaneously perform cooling and heating, a
relay unit is provided with a plurality of branch ports for a
refrigerant pipe, and indoor units are connected to the respective
branch ports. Because the relay unit needs to control flow
switching valves and the like based on whether the indoor units are
in operation or are stopped or whether the indoor units are
operating in a cooling mode or a heating mode, it is necessary to
perform the control by identifying which indoor unit is connected
to which branch port. Therefore, connected-branch-port numbers or
connected-indoor-unit numbers need to be set at the indoor units or
the relay unit by using DIP switches or the like.
[0005] However, when setting the connected-branch-port numbers or
the connected-indoor-unit numbers at the indoor units or the relay
unit by using DIP switches or the like, each indoor unit or the
relay unit requires setting means, such as a DIP switch, which
involves a problem in that the component cost is increased and a
troublesome task is required in the setting process. In addition,
there is another problem in that the operation cannot be performed
properly if this setting means is set incorrectly.
[0006] Furthermore, if the connections are to be automatically
determined by controlling the flow control valves and measuring
temperature changes in the indoor heat exchangers, as in Patent
Literature 1 described above, the temperature data of each indoor
heat exchanger needs to be transmitted to the relay unit by
communication. In order to allow for exchanging of such temperature
data, programs that use the same communication protocol need to be
provided for a transmission process performed by microcomputers of
controllers in the indoor units and a reception analysis process
performed by a microcomputer of a controller in the relay unit.
This is a problem in that there are limitations with respect to
indoor units that can be connected to the relay unit.
[0007] An example of limitations with respect to indoor units that
can be connected to the relay unit, as mentioned above, will be
described below.
[0008] FIG. 8 is a schematic diagram illustrating the configuration
of an indoor-unit controller and a relay-unit controller in the
related art provided with a function for controlling a flow control
valve and measuring a temperature change in an indoor heat
exchanger so as to automatically determine the connection. In FIG.
8, a relay-unit controller 63b and an indoor-unit controller 62 are
connected by transmission lines 71. The transmission lines 71
connect transmission circuits and reception circuits of the
relay-unit controller 63b and the indoor-unit controller 62. The
transmission circuit and the reception circuit in each controller
are connected to a microcomputer in the controller, and the
microcomputer performs a transmission process and a reception
analysis process.
[0009] FIG. 9 illustrates the flow of data when transmitting
temperature data of an indoor heat exchanger from the indoor-unit
controller 62 to the relay-unit controller 63b in the related art.
First, the temperature data is converted into a transmittable
digital signal by a transmission process performed by the
indoor-unit controller 62. Furthermore, the digital signal is
converted into a signal waveform by the transmission circuit, and
the signal waveform is transmitted to the relay unit via the
transmission line. In the relay-unit controller 63b, the reception
circuit reversely-converts the signal waveform into a digital
signal. Furthermore, the digital signal is reversely-converted into
temperature data by a reception analysis process so that the
temperature data can be received.
[0010] Accordingly, in the related art, programs that use the same
communication protocol need to be provided for both of the
transmission process performed by the microcomputer in the
indoor-unit controller 62 and the reception analysis process
performed by the microcomputer in the relay-unit controller 63b in
order to perform transmission and reception of the temperature
data.
[0011] Moreover, expensive circuit configurations are necessary
because the reception circuit in the relay-unit controller 63b and
the transmission circuit in the indoor-unit controller 62 need to
be connectable to each other and also need to satisfy limiting
conditions with respect to the operating speed.
[0012] In the related art, the relay unit and each indoor unit are
connectable only if the combination thereof satisfies the limiting
conditions thereof. This is a problem in that the units cannot be
readily connected if they are products provided by different
manufacturers.
[0013] In addition, there is another problem in that the
configuration for the communication between the relay unit and each
indoor unit is complicated.
[0014] The present invention has been made to solve the
aforementioned problems, and a first object thereof is to provide a
refrigerating and air-conditioning apparatus that achieves reduced
limitations with respect to the communication of indoor units and
can identify which indoor unit is connected to each branch
port.
[0015] A second object is to provide a refrigerating and
air-conditioning apparatus that can detect a setting error with
respect to the connection between each branch port and each indoor
unit.
Solution to Problem
[0016] A refrigerating and air-conditioning apparatus according to
the present invention includes a refrigeration cycle that makes a
refrigerant circulate therethrough by connecting a compressor, a
heat-source-side heat exchanger, at least one expansion valve, and
at least one intermediate heat exchanger; and a heat-medium circuit
that makes a heat medium circulate therethrough by connecting at
least one pump, a plurality of use-side heat exchangers, and the
intermediate heat exchanger. The at least one intermediate heat
exchanger and the pump are accommodated in a relay unit. The
plurality of use-side heat exchangers are accommodated in
respective indoor units. Each indoor unit includes an indoor-unit
controller that performs on-off control for operation performed by
the use-side heat exchanger for exchanging heat between the heat
medium and a thermal load. The relay unit includes a plurality of
branch ports that are connected to the plurality of use-side heat
exchangers and make the heat medium circulate to the use-side heat
exchangers, outlet temperature sensors that are provided for the
respective branch ports and each detect an outlet temperature of
the heat medium flowing out of the branch port to the corresponding
use-side heat exchanger, inlet temperature sensors that are
provided for the respective branch ports and each detect an inlet
temperature of the heat medium flowing into the branch port from
the corresponding use-side heat exchanger, and a relay-unit
controller that is connected to the indoor-unit controllers by a
transmission line and controls operation of each indoor-unit by
transmitting an operation command or a stop command thereto via the
transmission line. The relay-unit controller makes the indoor units
operate on a one-by-one basis and identifies which of the indoor
units is connected to each branch port on the basis of a difference
between the inlet temperature and the outlet temperature at the
branch port.
Advantageous Effects of Invention
[0017] The present invention can achieve reduced limitations with
respect to the communication of indoor units and can identify which
indoor unit is connected to each branch port.
BRIEF DESCRIPTION OF DRAWINGS
[0018] FIG. 1 is a schematic circuit diagram illustrating the
configuration of a refrigerating and air-conditioning apparatus
according to Embodiment 1 of the present invention.
[0019] FIG. 2 is a schematic diagram illustrating the configuration
of a relay-unit controller and an indoor-unit controller according
to Embodiment 1 of the present invention.
[0020] FIG. 3 is a flowchart illustrating the flow of an process of
automatic determination of connected branch ports to indoor units
in the refrigerating and air-conditioning apparatus according to
Embodiment 1 of the present invention.
[0021] FIG. 4 is a schematic circuit diagram illustrating the
configuration of a refrigerating and air-conditioning apparatus
according to Embodiment 2 of the present invention.
[0022] FIG. 5 is a flowchart illustrating the flow of an process of
automatic determination of connected branch ports to indoor units
in the refrigerating and air-conditioning apparatus according to
Embodiment 2 of the present invention.
[0023] FIG. 6 is a schematic circuit diagram illustrating the
configuration of a refrigerating and air-conditioning apparatus
according to Embodiment 3 of the present invention.
[0024] FIG. 7 is a flowchart illustrating the flow of an process of
automatic determination of connected branch ports to indoor units
in the refrigerating and air-conditioning apparatus according to
Embodiment 3 of the present invention.
[0025] FIG. 8 is a schematic diagram illustrating the configuration
of an indoor-unit controller and a relay-unit controller in the
related art provided with a function for controlling a flow control
valve and measuring a temperature change in an indoor heat
exchanger so as to automatically determine the connection.
[0026] FIG. 9 illustrates the flow of data when transmitting
temperature data of the indoor heat exchanger from an indoor-unit
controller 62 to a relay-unit controller 63b in the related
art.
DESCRIPTION OF EMBODIMENTS
Embodiment 1
[0027] Embodiment 1 relates to a refrigerating and air-conditioning
apparatus that performs an process of automatic determination of
connected branch ports to indoor units during trial operation
performed after installation of the apparatus.
[0028] FIG. 1 is a schematic circuit diagram illustrating the
configuration of the refrigerating and air-conditioning apparatus
according to Embodiment 1 of the present invention. As shown in
FIG. 1, the refrigerating and air-conditioning apparatus includes a
single heat source device 1 serving as a heat source unit, a
plurality of indoor units 2, and a relay unit 3 interposed between
the heat source device 1 and the indoor units 2.
[0029] The heat source device 1 accommodates a compressor 10, a
four-way valve 11, a heat-source-side heat exchanger 12, and an
accumulator 17 that are connected in series by a refrigerant pipe
4, and serves as a system that supplies required heat by means of a
refrigerant.
[0030] The indoor units 2 are individually equipped with use-side
heat exchangers 26. The use-side heat exchangers 26 are connected
to stop valves 24 and flow control valves 25 in a second relay unit
3b via pipes 5. The indoor units 2 transfer heat from a heat medium
circulated by the use-side heat exchangers 26 to indoor air by heat
exchange. The heat medium used may be water, an antifreeze, or the
like. In Embodiment 1, water is used as the heat medium.
[0031] The relay unit 3 is constituted of a first relay unit 3a and
the second relay unit 3b that are accommodated in separate
housings. The first relay unit 3a is provided with a gas-liquid
separator 14 and an expansion valve 16e, and separates a
transported refrigerant into three, that is, high-pressure gas,
intermediate-pressure liquid, and low-pressure gas and supplies the
refrigerant as a heat source for cooling and heating. The second
relay unit 3b is provided with two intermediate heat exchangers 15,
four expansion valves 16, two pumps 21, four flow switching valves
22, four flow switching valves 23, four stop valves 24, and four
flow control valves 25. The second relay unit 3b transfers required
heat from a cooling or heating refrigerant to water and causes the
water storing a required amount of heat to circulate to a
heat-medium circuit (water circuit).
[0032] The second relay unit 3b is further provided with two first
temperature sensors 31, two second temperature sensors 32, four
third temperature sensors 33, four fourth temperature sensors 34, a
fifth temperature sensor 35, a pressure sensor 36, a sixth
temperature sensor 37, and a seventh temperature sensor 38. The
four third temperature sensors 33 (third temperature sensors 33a to
33d) are provided at the inlet side of heat-medium passages of the
use-side heat exchangers 26, are configured to detect the
temperature of the heat medium flowing into the use-side heat
exchangers 26, and may be formed of thermistors or the like. The
number of third temperature sensors 33 provided corresponds the
number of (four, in this case) indoor units 2 installed. In line
with the indoor units 2, the third temperature sensor 33a, the
third temperature sensor 33b, the third temperature sensor 33c, and
the third temperature sensor 33d are shown in that order from the
lower side of the drawing.
[0033] The third temperature sensors 33 correspond to "inlet
temperature sensors" in the present invention.
[0034] The four fourth temperature sensors 34 (fourth temperature
sensors 34a to 34d) are provided at the outlet side of the
heat-medium passages of the use-side heat exchangers 26, are
configured to detect the temperature of the heat medium flowing out
of the use-side heat exchangers 26, and may be formed of
thermistors or the like. The number of fourth temperature sensors
34 provided corresponds to the number of (four, in this case)
indoor units 2 installed. In line with the indoor units 2, the
fourth temperature sensor 34a, the fourth temperature sensor 34b,
the fourth temperature sensor 34c, and the fourth temperature
sensor 34d are shown in that order from the lower side of the
drawing.
[0035] The fourth temperature sensors 34 correspond to "outlet
temperature sensors" in the present invention.
[0036] The pipes 5 that guide the water serving as a heat medium
include a pipe (referred to as "pipe 5a" hereinafter) that is
connected to the intermediate heat exchanger 15a and a pipe
(referred to as "pipe 5b" hereinafter) that is connected to the
intermediate heat exchanger 15b. The pipe 5a and the pipe 5b each
branch off into pipe segments (four pipe segments, in this case) in
accordance with the number of indoor units 2 connectable to the
relay unit 3. Combinations of branch pipe segments of the pipes 5a
and 5b that are connectable to the indoor units 2a to 2d will be
referred to as branch ports 6a to 6d. The branch ports 6a to 6d are
connected to each other by the flow switching valves 22, the flow
switching valves 23, and the flow control valves 25. By controlling
the flow switching valves 22 and the flow switching valves 23, the
heat medium guided through the pipe 5a can be made to flow into the
use-side heat exchangers 26, or the heat medium guided through the
pipe 5b can be made to flow into the use-side heat exchangers
26.
[0037] The heat source device 1 is provided with a controller 61
that controls the operation of each of the devices included in the
heat source device 1. The indoor units 2a to 2d are respectively
provided with indoor-unit controllers 62a to 62d that control the
operation of each of the devices included in each of the indoor
units 2a to 2d. The relay units 3a and 3b are respectively provided
with relay-unit controllers 63a and 63b that control the operation
of each of the devices included in the relay units 3a and 3b. The
relay-unit controller 63b is provided with a switch 64 that is to
be operated when commencing the automatic determination process for
branch ports.
[0038] The controller 61, the indoor-unit controllers 62a to 62d,
and the relay-unit controllers 63a and 63b are capable of
exchanging signals with each other.
[0039] The number of connected heat source devices 1, indoor units
2, and relay units 3 is not limited to that shown in the
drawing.
[0040] The indoor units 2 are not limited to air-conditioning
units, and may alternatively be hot-water-supply units.
[0041] Operation modes executed by the refrigerating and
air-conditioning apparatus 100 will now be described.
[0042] The refrigerating and air-conditioning apparatus 100 can
perform cooling operation or heating operation in each indoor unit
2. Specifically, the refrigerating and air-conditioning apparatus
100 can perform the same operation in all of the indoor units 2 or
perform different operations among the indoor units 2. Four
operation modes executable by the refrigerating and
air-conditioning apparatus 100, that is, a cooling only operation
mode in which all of the driven indoor units 2 perform the cooling
operation, a heating only operation mode in which all of the driven
indoor units 2 perform the heating operation, a cooling main
operation mode in which the cooling load is the greater, and a
heating main operation mode in which the heating load is the
greater, will be described below together with the flow of the
refrigerant.
Cooling Only Operation Mode
[0043] The following description relates to an example of a cooling
only operation mode in a case where a cooling load is generated
only in a use-side heat exchanger 26a and a use-side heat exchanger
26b.
[0044] In the case of the cooling only operation mode, the four-way
valve 11 in the heat source device 1 is switched so that the
refrigerant discharged from the compressor 10 flows into the
heat-source-side heat exchanger 12. In the relay unit 3, the pump
21a is stopped, the pump 21b is driven, the stop valve 24a and the
stop valve 24b are opened, and the stop valve 24c and the stop
valve 24d are closed, so that the heat medium circulates between
the intermediate heat exchanger 15b and the corresponding use-side
heat exchangers 26 (the use-side heat exchanger 26a and the
use-side heat exchanger 26b). In this state, the operation of the
compressor 10 commences.
[0045] First, the flow of the refrigerant in a refrigeration cycle
will be described.
[0046] A low-temperature low-pressure gas refrigerant is compressed
by the compressor 10 and is discharged therefrom as a
high-temperature high-pressure gas refrigerant. The
high-temperature high-pressure gas refrigerant discharged from the
compressor 10 travels through the four-way valve 11 so as to flow
into the heat-source-side heat exchanger 12. Then, the refrigerant
condenses and liquefies while transferring heat to outdoor air at
the heat-source-side heat exchanger 12, thereby becoming a
high-pressure liquid refrigerant. The high-pressure liquid
refrigerant flowing out of the heat-source-side heat exchanger 12
flows out of the heat source device 1 via a check valve, and then
travels through the refrigerant pipe 4 so as to flow into the first
relay unit 3a. The high-pressure liquid refrigerant flowing into
the first relay unit 3a flows into the gas-liquid separator 14 and
then travels through the expansion valve 16e before flowing into
the second relay unit 3b.
[0047] The refrigerant flowing into the second relay unit 3b is
expanded by being throttled by an expansion valve 16a, thereby
becoming a low-temperature low-pressure two-phase gas-liquid
refrigerant. This two-phase gas-liquid refrigerant flows into the
intermediate heat exchanger 15b functioning as an evaporator and
cools the heat medium circulating through the heat-medium circuit
by receiving heat from the heat medium, thereby becoming a
low-temperature low-pressure gas refrigerant. The gas refrigerant
flowing out of the intermediate heat exchanger 15b flows out of the
second relay unit 3b and the first relay unit 3a after traveling
through an expansion valve 16c, and then travels through the
refrigerant pipe 4 so as to flow into the heat source device 1. The
refrigerant flowing into the heat source device 1 travels through a
check valve and is suctioned into the compressor 10 again via the
four-way valve 11 and the accumulator 17. The expansion valve 16b
and the expansion valve 16d are set to small opening degrees so as
to prevent the refrigerant from flowing therethrough, whereas the
expansion valve 16c is completely opened so as to prevent the
occurrence of pressure loss.
[0048] Next, the flow of the heat medium in the heat-medium circuit
will be described.
[0049] In the cooling only operation mode, the heat medium
circulates via the pipe 5b since the pump 21a is stopped. The heat
medium cooled by the refrigerant at the intermediate heat exchanger
15b is made to flow through the pipe 5b by the pump 21b. The heat
medium pressurized by and flowing out of the pump 21b travels
through the stop valves 24 (the stop valve 24a and the stop valve
24b) via the flow switching valves 22 (the flow switching valve 22a
and the flow switching valve 22b) so as to flow into the use-side
heat exchangers 26 (the use-side heat exchanger 26a and the
use-side heat exchanger 26b). Then, the heat medium receives heat
from indoor air (thermal load) at the use-side heat exchangers 26,
thereby cooling an air-conditioning target area, such as an indoor
area, where the indoor units 2 are installed.
[0050] Subsequently, the heat medium flowing out of the use-side
heat exchangers 26 flows into the flow control valves 25 (the flow
control valve 25a and the flow control valve 25b). In this case,
with the functions of the flow control valves 25, only an amount of
heat medium sufficient to cover the air-conditioning load required
in the air-conditioning target area, such as an indoor area, flows
into the use-side heat exchangers 26, whereas the remaining heat
medium bypasses the use-side heat exchangers 26 by flowing through
bypass pipes 27 (a bypass pipe 27a and a bypass pipe 27b).
[0051] The heat medium traveling through the bypass pipes 27 does
not contribute to heat exchange and merges with the heat medium
having traveled through the use-side heat exchangers 26. Then, the
heat medium flows into the intermediate heat exchanger 15b via the
flow switching valves 23 (the flow switching valve 23a and the flow
switching valve 23b), and is suctioned into the pump 21b again. The
air-conditioning load required in the air-conditioning target area,
such as an indoor area, can be covered by performing control such
that a temperature difference between the third temperature sensors
33 and the fourth temperature sensors 34 is maintained at a target
value.
[0052] In this case, since the heat medium does not need to flow
into use-side heat exchangers 26 with no thermal load (including
those in a thermostat-off state), the passages therefor are closed
by the corresponding stop valves 24, thereby preventing the heat
medium from flowing toward the use-side heat exchangers 26. Since
there is a thermal load in the use-side heat exchanger 26a and the
use-side heat exchanger 26b, the heat medium is made to flow into
these heat exchangers. In contrast, since there is no thermal load
in the use-side heat exchanger 26c and the use-side heat exchanger
26d, the corresponding stop valves 24c and 24d are closed. If a
cooling load is generated at the use-side heat exchanger 26c or the
use-side heat exchanger 26d, the stop valve 24c or the stop valve
24d may be opened so as to circulate the heat medium.
Heating Only Operation Mode
[0053] The following description relates to an example of a heating
only operation mode in a case where a heating load is generated
only in the use-side heat exchanger 26a and the use-side heat
exchanger 26b.
[0054] In the case of the heating only operation mode, the four-way
valve 11 in the heat source device 1 is switched so that the
refrigerant discharged from the compressor 10 flows into the relay
unit 3 without traveling through the heat-source-side heat
exchanger 12. In the relay unit 3, the pump 21a is driven, the pump
21b is stopped, the stop valve 24a and the stop valve 24b are
opened, and the stop valve 24c and the stop valve 24d are closed,
so that the heat medium circulates between the intermediate heat
exchanger 15a and the corresponding use-side heat exchangers 26
(the use-side heat exchanger 26a and the use-side heat exchanger
26b). In this state, the operation of the compressor 10
commences.
[0055] First, the flow of the refrigerant in the refrigeration
cycle will be described.
[0056] A low-temperature low-pressure gas refrigerant is compressed
by the compressor 10 and is discharged therefrom as a
high-temperature high-pressure gas refrigerant. The
high-temperature high-pressure gas refrigerant discharged from the
compressor 10 travels through the four-way valve 11, is guided
through the refrigerant pipe 4, and then passes through a check
valve so as to flow out of the heat source device 1. The
high-temperature high-pressure gas refrigerant flowing out of the
heat source device 1 travels through the refrigerant pipe 4 so as
to flow into the first relay unit 3a. The high-temperature
high-pressure gas refrigerant flowing into the first relay unit 3a
flows into the gas-liquid separator 14 and subsequently flows into
the intermediate heat exchanger 15a. The high-temperature
high-pressure gas refrigerant flowing into the intermediate heat
exchanger 15a condenses and liquefies while transferring heat to
the heat medium circulating through the heat-medium circuit,
thereby becoming a high-pressure liquid refrigerant.
[0057] The high-pressure liquid refrigerant flowing out of the
intermediate heat exchanger 15a is expanded by being throttled by
the expansion valve 16d, thereby turning into a low-temperature
low-pressure two-phase gas-liquid state. The two-phase gas-liquid
refrigerant throttled by the expansion valve 16d travels through
the expansion valve 16b and is guided through the refrigerant pipe
4 so as to flow into the heat source device 1 again. The
refrigerant flowing into the heat source device 1 flows into the
heat-source-side heat exchanger 12 functioning as an evaporator via
a check valve. Then, the refrigerant flowing into the
heat-source-side heat exchanger 12 receives heat from outdoor air
at the heat-source-side heat exchanger 12, thereby becoming a
low-temperature low-pressure gas refrigerant. The low-temperature
low-pressure gas refrigerant flowing out of the heat-source-side
heat exchanger 12 returns to the compressor 10 via the four-way
valve 11 and the accumulator 17. The expansion valve 16a, the
expansion valve 16c, and the expansion valve 16e are set to small
opening degrees so as to prevent the refrigerant from flowing
therethrough.
[0058] Next, the flow of the heat medium in the heat-medium circuit
will be described.
[0059] In the heating only operation mode, the heat medium
circulates via the pipe 5a since the pump 21b is stopped. The heat
medium heated by the refrigerant at the intermediate heat exchanger
15a is made to flow through the pipe 5a by the pump 21a. The heat
medium pressurized by and flowing out of the pump 21a travels
through the stop valves 24 (the stop valve 24a and the stop valve
24b) via the flow switching valves 22 (the flow switching valve 22a
and the flow switching valve 22b) so as to flow into the use-side
heat exchangers 26 (the use-side heat exchanger 26a and the
use-side heat exchanger 26b). Then, the heat medium transfers heat
to indoor air (thermal load) at the use-side heat exchangers 26,
thereby heating the air-conditioning target area, such as an indoor
area, where the indoor units 2 are installed.
[0060] Subsequently, the heat medium flowing out of the use-side
heat exchangers 26 flows into the flow control valves 25 (the flow
control valve 25a and the flow control valve 25b). In this case,
with the functions of the flow control valves 25, only an amount of
heat medium sufficient to cover the air-conditioning load required
in the air-conditioning target area, such as an indoor area, flows
into the use-side heat exchangers 26, whereas the remaining heat
medium bypasses the use-side heat exchangers 26 by flowing through
the bypass pipes 27 (the bypass pipe 27a and the bypass pipe
27b).
[0061] The heat medium traveling through the bypass pipes 27 does
not contribute to heat exchange and merges with the heat medium
having traveled through the use-side heat exchangers 26. Then, the
heat medium flows into the intermediate heat exchanger 15a via the
flow switching valves 23 (the flow switching valve 23a and the flow
switching valve 23b), and is suctioned into the pump 21a again. The
air-conditioning load required in the air-conditioning target area,
such as an indoor area, can be covered by performing control such
that a temperature difference between the third temperature sensors
33 and the fourth temperature sensors 34 is maintained at a target
value.
[0062] In this case, since the heat medium does not need to flow
into use-side heat exchangers 26 with no thermal load (including
those in a thermostat-off state), the passages therefor are closed
by the corresponding stop valves 24, thereby preventing the heat
medium from flowing toward the use-side heat exchangers 26. Since
there is a thermal load in the use-side heat exchanger 26a and the
use-side heat exchanger 26b, the heat medium is made to flow into
these heat exchangers. In contrast, since there is no thermal load
in the use-side heat exchanger 26c and the use-side heat exchanger
26d, the corresponding stop valves 24c and 24d are closed. If a
heating load is generated at the use-side heat exchanger 26c or the
use-side heat exchanger 26d, the stop valve 24c or the stop valve
24d may be opened so as to circulate the heat medium.
Cooling Main Operation Mode
[0063] The following description relates to an example of a cooling
main operation mode in a case where a heating load is generated at
the use-side heat exchanger 26a and a cooling load is generated at
the use-side heat exchanger 26b.
[0064] In the case of the cooling main operation mode, the four-way
valve 11 in the heat source device 1 is switched so that the
refrigerant discharged from the compressor 10 flows into the
heat-source-side heat exchanger 12. In the relay unit 3, the pump
21a and the pump 21b are driven, the stop valve 24a and the stop
valve 24b are opened, and the stop valve 24c and the stop valve 24d
are closed, so that the heat medium circulates between the
intermediate heat exchanger 15a and the use-side heat exchanger 26a
as well as between the intermediate heat exchanger 15b and the
use-side heat exchanger 26b. In this state, the operation of the
compressor 10 commences.
[0065] First, the flow of the refrigerant in the refrigeration
cycle will be described.
[0066] A low-temperature low-pressure gas refrigerant is compressed
by the compressor 10 and is discharged therefrom as a
high-temperature high-pressure gas refrigerant. The
high-temperature high-pressure gas refrigerant discharged from the
compressor 10 travels through the four-way valve 11 so as to flow
into the heat-source-side heat exchanger 12. Then, the refrigerant
condenses by transferring heat to outdoor air at the
heat-source-side heat exchanger 12, thereby becoming a two-phase
gas-liquid refrigerant. The two-phase gas-liquid refrigerant
flowing out of the heat-source-side heat exchanger 12 flows out of
the heat source device 1 via a check valve, and then travels
through the refrigerant pipe 4 so as to flow into the first relay
unit 3a. The two-phase gas-liquid refrigerant flowing into the
first relay unit 3a flows into the gas-liquid separator 14 where
the refrigerant is separated into a gas refrigerant and a liquid
refrigerant, which then flow into the second relay unit 3b.
[0067] The gas refrigerant separated at the gas-liquid separator 14
flows into the intermediate heat exchanger 15a. The gas refrigerant
flowing into the intermediate heat exchanger 15a condenses and
liquefies while transferring heat to the heat medium circulating
through the heat-medium circuit, thereby becoming a liquid
refrigerant. The liquid refrigerant flowing out of the intermediate
heat exchanger 15b travels through the expansion valve 16d. On the
other hand, the liquid refrigerant separated at the gas-liquid
separator 14 travels through the expansion valve 16e, merges with
the liquid refrigerant condensed and liquefied at the intermediate
heat exchanger 15a and having traveled through the expansion valve
16d, and is expanded by being throttled by the expansion valve 16a
so as to flow into the intermediate heat exchanger 15b as a
low-temperature low-pressure two-phase gas-liquid refrigerant.
[0068] At the intermediate heat exchanger 15b functioning as an
evaporator, this two-phase gas-liquid refrigerant receives heat
from the heat medium circulating through the heat-medium circuit so
as to become a low-temperature low-pressure gas refrigerant while
cooling the heat medium. The gas refrigerant flowing out of the
intermediate heat exchanger 15b travels through the expansion valve
16c and then flows out of the second relay unit 3b and the first
relay unit 3a so as to flow into the heat source device 1 via the
refrigerant pipe 4. The refrigerant having flowed into the heat
source device 1 travels through a check valve and is suctioned into
the compressor 10 again via the four-way valve 11 and the
accumulator 17. The expansion valve 16b is set to a small opening
degree so as to prevent the refrigerant from flowing therethrough,
whereas the expansion valve 16c is completely opened so as to
prevent the occurrence of pressure loss.
[0069] Next, the flow of the heat medium in the heat-medium circuit
will be described.
[0070] In the cooling main operation mode, the heat medium
circulates via both the pipe 5a and the pipe 5b since the pump 21a
and the pump 21b are both driven. The heat medium heated by the
refrigerant at the intermediate heat exchanger 15a is made to flow
through the pipe 5a by the pump 21a. The heat medium cooled by the
refrigerant at the intermediate heat exchanger 15b is made to flow
through the pipe 5b by the pump 21b.
[0071] The heat medium pressurized by and flowing out of the pump
21a travels through the stop valve 24a via the flow switching valve
22a so as to flow into the use-side heat exchanger 26a. Then, the
heat medium transfers heat to indoor air (thermal load) at the
use-side heat exchanger 26a, thereby heating the air-conditioning
target area, such as an indoor area, where the indoor unit 2 is
installed. The heat medium pressurized by and flowing out of the
pump 21b travels through the stop valve 24b via the flow switching
valve 22b so as to flow into the use-side heat exchanger 26b. Then,
the heat medium receives heat from indoor air (thermal load) at the
use-side heat exchanger 26b, thereby cooling the air-conditioning
target area, such as an indoor area, where the indoor unit 2 is
installed.
[0072] The heat medium having performed the heating flows into the
flow control valve 25a. In this case, with the function of the flow
control valve 25a, only an amount of heat medium sufficient to
cover the air-conditioning load required in the air-conditioning
target area flows into the use-side heat exchanger 26a, whereas the
remaining heat medium bypasses the use-side heat exchanger 26a by
flowing through the bypass pipe 27a. The heat medium traveling
through the bypass pipe 27a does not contribute to heat exchange
and merges with the heat medium having traveled through the
use-side heat exchanger 26a. Then, the heat medium flows into the
intermediate heat exchanger 15a via the flow switching valve 23a,
and is suctioned into the pump 21a again.
[0073] Likewise, the heat medium having performed the cooling flows
into the flow control valve 25b. In this case, with the function of
the flow control valve 25b, only an amount of heat medium
sufficient to cover the air-conditioning load required in the
air-conditioning target area flows into the use-side heat exchanger
26b, whereas the remaining heat medium bypasses the use-side heat
exchanger 26b by flowing through the bypass pipe 27b. The heat
medium traveling through the bypass pipe 27b does not contribute to
heat exchange and merges with the heat medium having traveled
through the use-side heat exchanger 26b. Then, the heat medium
flows into the intermediate heat exchanger 15b via the flow
switching valve 23b, and is suctioned into the pump 21b again.
[0074] During this time, the warm heat medium (the heat medium to
be used for the heating load) and the cool heat medium (the heat
medium to be used for the cooling load) respectively flow into the
use-side heat exchanger 26a with the heating load and the use-side
heat exchanger 26b with the cooling load without mixing with each
other due to the functions of the flow switching valves 22 (the
flow switching valve 22a and the flow switching valve 22b) and the
flow switching valves 23 (the flow switching valve 23a and the flow
switching valve 23b). The air-conditioning load required in the
air-conditioning target area, such as an indoor area, can be
covered by performing control such that a temperature difference
between the third temperature sensors 33 and the fourth temperature
sensors 34 is maintained at a target value.
[0075] In this case, since the heat medium does not need to flow
into use-side heat exchangers 26 with no thermal load (including
those in a thermostat-off state), the passages therefor are closed
by the corresponding stop valves 24, thereby preventing the heat
medium from flowing toward the use-side heat exchangers 26.
Referring to FIG. 6, since there is a thermal load in the use-side
heat exchanger 26a and the use-side heat exchanger 26b, the heat
medium is made to flow into these heat exchangers. In contrast,
since there is no thermal load in the use-side heat exchanger 26c
and the use-side heat exchanger 26d, the corresponding stop valves
24c and 24d are closed. If a heating load or a cooling load is
generated at the use-side heat exchanger 26c or the use-side heat
exchanger 26d, the stop valve 24c or the stop valve 24d may be
opened so as to circulate the heat medium.
Heating Main Operation Mode
[0076] The following description relates to an example of a heating
main operation mode in a case where a heating load is generated at
the use-side heat exchanger 26a and a cooling load is generated at
the use-side heat exchanger 26b.
[0077] In the case of the heating main operation mode, the four-way
valve 11 in the heat source device 1 is switched so that the
refrigerant discharged from the compressor 10 flows into the relay
unit 3 without traveling through the heat-source-side heat
exchanger 12. In the relay unit 3, the pump 21a and the pump 21b
are driven, the stop valve 24a and the stop valve 24b are opened,
and the stop valve 24c and the stop valve 24d are closed, so that
the heat medium circulates between the intermediate heat exchanger
15a and the use-side heat exchanger 26a as well as between the
intermediate heat exchanger 15b and the use-side heat exchanger
26b. In this state, the operation of the compressor 10
commences.
[0078] First, the flow of the refrigerant in the refrigeration
cycle will be described.
[0079] A low-temperature low-pressure refrigerant is compressed by
the compressor 10 and is discharged therefrom as a high-temperature
high-pressure gas refrigerant. The high-temperature high-pressure
gas refrigerant discharged from the compressor 10 travels through
the four-way valve 11, is guided through the refrigerant pipe 4,
and then passes through a check valve so as to flow out of the heat
source device 1. The high-temperature high-pressure gas refrigerant
flowing out of the heat source device 1 travels through the
refrigerant pipe 4 so as to flow into the first relay unit 3a. The
high-temperature high-pressure gas refrigerant having flowed into
the first relay unit 3a flows into the gas-liquid separator 14 and
subsequently flows into the intermediate heat exchanger 15a. The
high-temperature high-pressure gas refrigerant having flowed into
the intermediate heat exchanger 15a condenses and liquefies while
transferring heat to the heat medium circulating through the
heat-medium circuit, thereby becoming a high-pressure liquid
refrigerant.
[0080] The high-pressure liquid refrigerant flowing out of the
intermediate heat exchanger 15a is expanded by being throttled by
the expansion valve 16d, thereby turning into a low-temperature
low-pressure two-phase gas-liquid state. The two-phase gas-liquid
refrigerant throttled by the expansion valve 16d is distributed to
a passage extending through the expansion valve 16a and a passage
extending through the expansion valve 16b. The refrigerant
traveling through the expansion valve 16a is further expanded by
the expansion valve 16a so as to become a low-temperature
low-pressure two-phase gas-liquid refrigerant, which then flows
into the intermediate heat exchanger 15b functioning as an
evaporator. Then, the refrigerant having flowed into the
intermediate heat exchanger 15b receives heat from the heat medium
at the intermediate heat exchanger 15b, thereby becoming a
low-temperature low-pressure gas refrigerant. The low-temperature
low-pressure gas refrigerant flowing out of the intermediate heat
exchanger 15b travels through the expansion valve 16c.
[0081] On the other hand, the refrigerant throttled by the
expansion valve 16d and flowing to the expansion valve 16b merges
with the refrigerant traveling through the intermediate heat
exchanger 15b and the expansion valve 16c, thereby becoming a
low-temperature low-pressure refrigerant with a greater quality.
Then, the merged refrigerant flows out of the second relay unit 3b
and the first relay unit 3a and then travels through the
refrigerant pipe 4 so as to flow into the heat source device 1. The
refrigerant having flowed into the heat source device 1 flows into
the heat-source-side heat exchanger 12 functioning as an evaporator
via a check valve. Then, the refrigerant having flowed into the
heat-source-side heat exchanger 12 receives heat from outdoor air
at the heat-source-side heat exchanger 12, thereby becoming a
low-temperature low-pressure gas refrigerant. The low-temperature
low-pressure gas refrigerant flowing out of the heat-source-side
heat exchanger 12 returns to the compressor 10 via the four-way
valve 11 and the accumulator 17. The expansion valve 16e is set to
a small opening degree so as to prevent the refrigerant from
flowing therethrough.
[0082] Next, the flow of the heat medium in the heat-medium circuit
will be described.
[0083] In the heating main operation mode, the heat medium
circulates via both the pipe 5a and the pipe 5b since the pump 21a
and the pump 21b are both driven. The heat medium heated by the
refrigerant at the intermediate heat exchanger 15a is made to flow
through the pipe 5a by the pump 21a. The heat medium cooled by the
refrigerant at the intermediate heat exchanger 15b is made to flow
through the pipe 5b by the pump 21b.
[0084] The heat medium pressurized by and flowing out of the pump
21a travels through the stop valve 24a via the flow switching valve
22a so as to flow into the use-side heat exchanger 26a. Then, the
heat medium transfers heat to indoor air (thermal load) at the
use-side heat exchanger 26a, thereby heating the air-conditioning
target area, such as an indoor area, where the indoor unit 2 is
installed. The heat medium pressurized by and flowing out of the
pump 21b travels through the stop valve 24b via the flow switching
valve 22b so as to flow into the use-side heat exchanger 26b. Then,
the heat medium receives heat from indoor air (thermal load) at the
use-side heat exchanger 26b, thereby cooling the air-conditioning
target area, such as an indoor area, where the indoor unit 2 is
installed.
[0085] The heat medium flowing out of the use-side heat exchanger
26a flows into the flow control valve 25a. In this case, with the
function of the flow control valve 25a, only an amount of heat
medium sufficient to cover the air-conditioning load required in
the air-conditioning target area, such as an indoor area, flows
into the use-side heat exchanger 26a, whereas the remaining heat
medium bypasses the use-side heat exchanger 26a by flowing through
the bypass pipe 27a. The heat medium traveling through the bypass
pipe 27a does not contribute to heat exchange and merges with the
heat medium having traveled through the use-side heat exchanger
26a. Then, the heat medium flows into the intermediate heat
exchanger 15a via the flow switching valve 23a, and is suctioned
into the pump 21a again.
[0086] Likewise, the heat medium flowing out of the use-side heat
exchanger 26b flows into the flow control valve 25b. In this case,
with the function of the flow control valve 25b, only an amount of
heat medium sufficient to cover the air-conditioning load required
in the air-conditioning target area, such as an indoor area, flows
into the use-side heat exchanger 26b, whereas the remaining heat
medium bypasses the use-side heat exchanger 26b by flowing through
the bypass pipe 27b. The heat medium traveling through the bypass
pipe 27b does not contribute to heat exchange and merges with the
heat medium having traveled through the use-side heat exchanger
26b. Then, the heat medium flows into the intermediate heat
exchanger 15b via the flow switching valve 23b, and is suctioned
into the pump 21b again.
[0087] During this time, the warm heat medium and the cool heat
medium respectively flow into the use-side heat exchanger 26a with
the heating load and the use-side heat exchanger 26b with the
cooling load without mixing with each other due to the functions of
the flow switching valves 22 (the flow switching valve 22a and the
flow switching valve 22b) and the flow switching valves 23 (the
flow switching valve 23a and the flow switching valve 23b). The
air-conditioning load required in the air-conditioning target area,
such as an indoor area, can be covered by performing control such
that a temperature difference between the third temperature sensors
33 and the fourth temperature sensors 34 is maintained at a target
value.
[0088] In this case, since the heat medium does not need to flow
into use-side heat exchangers 26 with no thermal load (including
those in a thermostat-off state), the passages therefor are closed
by the corresponding stop valves 24, thereby preventing the heat
medium from flowing toward the use-side heat exchangers 26.
Referring to FIG. 7, since there is a thermal load in the use-side
heat exchanger 26a and the use-side heat exchanger 26b, the heat
medium is made to flow into these heat exchangers. In contrast,
since there is no thermal load in the use-side heat exchanger 26c
and the use-side heat exchanger 26d, the corresponding stop valves
24c and 24d are closed. If a heating load or a cooling load is
generated at the use-side heat exchanger 26c or the use-side heat
exchanger 26d, the stop valve 24c or the stop valve 24d may be
opened so as to circulate the heat medium.
[0089] Accordingly, when a heating load is generated at the
use-side heat exchangers 26a to 26d, the corresponding flow
switching valves 22a to 22d and the corresponding flow switching
valves 23a to 23d are switched to passages that are connected to
the intermediate heat exchanger 15a for heating. If a cooling load
is generated at the use-side heat exchangers 26a to 26d, the
corresponding flow switching valves 22a to 22d and the
corresponding flow switching valves 23a to 23d are switched to
passages that are connected to the intermediate heat exchanger 15b
for cooling. Consequently, heating operation or cooling operation
can be performed freely in each indoor unit 2.
[0090] The flow switching valves 22a to 22d and the flow switching
valves 23a to 23d may each be a device that can switch passages,
such as a device that can switch a three-way passage, like a
three-way valve, or a combination of two devices, like two on-off
valves, which can open and close a two-way passage. Alternatively,
the flow switching valves 22a to 22d and the flow switching valves
23a to 23d may each be a device that can change the flow rate in a
three-way passage, such as a stepping-motor-driven mixing valve, or
a combination of two devices, such as electronic expansion valves,
which can change the flow rate in a two-way passage. In this case,
the occurrence of water hammer caused by sudden opening or closing
of a passage can also be prevented.
Configuration of Controllers
[0091] FIG. 2 is a schematic diagram illustrating the configuration
of a relay-unit controller and an indoor-unit controller according
to Embodiment 1 of the present invention.
[0092] As shown in FIG. 2, the relay-unit controller 63b includes a
control unit 300 within a microcomputer 300a, an output circuit
301, an input circuit 302, an input circuit 303, and an input
circuit 304. Each of the indoor-unit controllers 62 (the
indoor-unit controllers 62a to 62d) includes a control unit 200, an
input circuit 201, an output circuit 202, and an output circuit
203.
[0093] The relay-unit controller 63b and each indoor-unit
controller 62 are connected by three transmission lines 71. A
transmission line 71a connects the output circuit 301 of the
relay-unit controller 63b to the input circuit 201 of the
indoor-unit controller 62. A transmission line 71b connects the
input circuit 302 of the relay-unit controller 63b to the output
circuit 202 of the indoor-unit controller 62. A transmission line
71c connects the input circuit 303 of the relay-unit controller 63b
to the output circuit 203 of the indoor-unit controller 62.
[0094] Although only one indoor-unit controller 62 is shown in FIG.
2, the indoor-unit controllers 62a of the indoor units have the
same configuration and are each connected to the relay-unit
controller 63b by three transmission lines 71. Furthermore, the
number of output circuits 301, input circuits 302, and input
circuits 303 provided in the relay-unit controller 63b correspond
to the number of indoor-unit controllers 62 connected thereto.
[0095] The output circuit 301 of the relay-unit controller 63b
transmits a binary signal corresponding to an operation command and
a stop command via the transmission line 71a in accordance with
output processing from the control unit 300. The binary signal is,
for example, an on/off signal that sets the operation command to a
predetermined voltage value and the stop command to an output value
of zero. The input circuit 201 of each indoor-unit controller 62
receives the binary signal via the transmission line 71a and inputs
the binary signal to the control unit 200. The control unit 200
starts or stops the operation of the indoor unit 2 on the basis of
the input binary signal. The expression "start the operation of the
indoor unit 2" refers to, for example, a state (thermostat-on
state) in which a fan and the like within the indoor unit 2 are
driven so as to facilitate heat exchange between the heat medium
and indoor air (thermal load) by the use-side heat exchanger 26.
The expression "stop the operation" refers to, for example, a state
(thermostat-off state) in which the driving of the fan and the like
within the indoor unit 2 is stopped so as not to facilitate heat
exchange between the heat medium and indoor air (thermal load) by
the use-side heat exchanger 26.
[0096] The output circuit 202 of the indoor-unit controller 62
transmits a binary signal corresponding to an operating state and a
stopped state of the indoor unit via the transmission line 71b in
accordance with output processing from the control unit 200. This
binary signal is, for example, an on/off signal that sets the
operating state to a predetermined voltage value and the stopped
state to an output value of zero. The input circuit 302 of the
relay-unit controller 63b receives the binary signal via the
transmission line 71b and inputs the binary signal to the control
unit 300. The control unit 300 determines whether the indoor unit 2
is in the operating state or the stopped state on the basis of the
input binary signal.
[0097] The output circuit 203 of the indoor-unit controller 62
transmits a binary signal corresponding to a heating mode and a
cooling mode of the indoor unit via the transmission line 71c in
accordance with output processing from the control unit 200. This
binary signal is, for example, an on/off signal that sets the
heating mode to a predetermined voltage value and the cooling mode
to an output value of zero. The input circuit 303 of the relay-unit
controller 63b receives the binary signal via the transmission line
71c and inputs the binary signal to the control unit 300. The
control unit 300 determines whether the indoor unit 2 is operating
in the heating mode or the cooling mode on the basis of the input
binary signal.
[0098] The input circuit 304 of the relay-unit controller 63b
inputs detection values of the third temperature sensors 33a to 33d
and the fourth temperature sensors 34a to 34d provided in the relay
unit 3 to the control unit 300. The control unit 300 performs a
process of automatic determination of connected branch ports on the
basis of input temperature data.
[0099] The control unit 300 may be achieved by software executed on
the microcomputer 300a but not limited to this. The control unit
300 may be achieved with hardware, such as a circuit device that
achieves the function of the control unit 300.
[0100] In each indoor-unit controller 62, the control unit 200 may
similarly be achieved by software executed on a microcomputer.
Alternatively, a relay circuit or the like may be used in place of
a microcomputer.
[0101] With the above configuration, the relay-unit controller 63b
and each indoor-unit controller 62 can exchange information by
inputting and outputting binary signals (on/off signals).
[0102] Therefore, as compared with the configuration in FIG. 8,
which is a related-art technology, the need for performing
digital-signal conversion during a transmission process and a
reception analysis process during reception can be eliminated, so
that a program of the microcomputer 300a in the relay-unit
controller 63b is simplified, thereby reducing limitations with
respect to connectable devices.
[0103] Furthermore, the input circuits and the output circuits can
be achieved at a lower cost, as compared with the configuration in
FIG. 8, which is a related-art technology. Moreover, the
indoor-unit controllers 62 can also be achieved at a lower cost
since microcomputers are not used therein.
[0104] In normal operation performed after the process of automatic
determination of connected branch ports, to be described later, the
indoor-unit controllers 62 may start or stop the operation of the
indoor units 2 in response to commands from remote controllers or
the like provided in the indoor units 2.
[0105] In this case, the relay-unit controller 63b sets the
operation mode to be executed by the refrigerating and
air-conditioning apparatus 100 and switches the passages extending
to the use-side heat exchangers 26 by controlling the stop valves
24, the flow switching valves 22, the flow switching valves 23, and
the like so that hot water or cold water is supplied from the
corresponding branch ports 6 in accordance with the binary signals
corresponding to the operating/stopped states and the binary
signals corresponding to the heating/cooling modes received from
the indoor-unit controllers 62.
[0106] Accordingly, even during the normal operation, the
relay-unit controller 63b and the indoor-unit controllers 62
communicate with each other only by input and output of binary
signals (on/off signals), so that limitations with respect to the
communication of the indoor units 2 that can be connected to the
relay unit 3 can be reduced.
[0107] The refrigerating and air-conditioning apparatus 100 having
the above configuration performs the process of automatic
determination of connected branch ports in which to identify which
indoor unit 2 is connected to which branch port 6 during trial
operation performed after installation of the apparatus.
[0108] Next, the operation of the process of automatic
determination of connected branch ports will be described.
Process of Automatic Determination of Connected Branch Ports
[0109] FIG. 3 is a flowchart illustrating the flow of the process
of automatic determination of connected branch ports of the indoor
units in the refrigerating and air-conditioning apparatus according
to Embodiment 1 of the present invention.
[0110] The refrigerating and air-conditioning apparatus 100
commences the automatic determination process when, for example,
the switch 64 provided in the relay unit 3 is operated.
[0111] In FIG. 3, step 101 to step 113 correspond to a process
performed by the relay unit 3.
[0112] In step 102, the relay unit 3 transmits a trial heating only
operation command to the heat source device 1 and the process
proceeds to step 103.
[0113] In step 103, the heat source device 1 receives the trial
heating only operation command from the relay unit 3 and starts
operating in the heating only operation mode described above.
[0114] Furthermore, the relay unit 3 starts operating in the
heating only operation mode and supplies hot water (heated heat
medium) to all of the branch ports 6a to 6d regardless of the
operation modes (heating/cooling) of the indoor units 2.
Subsequently, the process proceeds to step 104.
[0115] In step 104, an operation command is transmitted to indoor
units 2 to which an operation command is not transmitted yet. Here,
no operation command has been transmitted yet, and an operation
command is transmitted to the first indoor unit 2a via the
transmission line 71a so that the indoor unit 2a begins to operate.
Subsequently, the process proceeds to step 105. Thus, the hot water
and indoor air exchange heat with each other in the use-side heat
exchanger 26a of the indoor unit 2a, thereby heating the indoor
area or the like in which the indoor unit 2a is installed (heating
mode).
[0116] In step 105, after waiting for a predetermined time to
elapse, the process proceeds to step 106.
[0117] In step 106, current water-temperature data of all of the
branch ports 6a to 6d are acquired. In this case, temperatures T33a
to T33d of the four third temperature sensors 33a to 33d and
temperatures T34a to T34d of the four fourth temperature sensors
34a to 34d are acquired. The process then proceeds to step 107.
[0118] In step 107, the branch-port determination process is
performed. In this case, changes in the data of the temperatures
T33a to T33d of the four third temperature sensors 33a to 33d and
the temperatures T34a to T34d of the four fourth temperature
sensors 34a to 34d are checked.
[0119] The temperatures detected by the third temperature sensors
33a to 33d are temperatures (outlet temperatures) of hot water
supplied to the use-side heat exchangers 26a to 26d from the branch
ports 6a to 6d.
[0120] The temperatures detected by the fourth temperature sensors
34a to 34d are temperatures (inlet temperatures) of hot water
returning to the branch ports 6a to 6d from the use-side heat
exchangers 26a to 26d.
[0121] If a temperature difference between the inlet temperature
and the outlet temperature at each of the branch ports 6a to 6d is
defined as .DELTA.Ti (i=a, b, c, or d), the following expression
stands:
temperature difference .DELTA.Ti=T33i-T34i(i=a,b,c,or d)
[0122] In the indoor unit 2a operating in the heating mode, because
heat is transferred from the hot water at the use-side heat
exchanger 26a, the temperature difference .DELTA.T at the branch
port 6 connected to the indoor unit 2a is a positive value.
[0123] On the other hand, in the indoor units 2b to 2d that are in
a stopped state, because there is little receiving or transferring
of heat to the hot water at the use-side heat exchangers 26b to
26d, the temperature difference .DELTA.T at each of the branch
ports 6 connected to the indoor units 2b to 2d is a value whose
absolute value is small.
[0124] Accordingly, if a certain temperature difference .DELTA.T is
a positive value that is larger than a predetermined determination
value, the relay unit 3 determines that an indoor unit 2 currently
in operation is connected to the branch port 6 at which the
aforementioned temperature difference .DELTA.T is detected. On the
other hand, if the value of a temperature difference .DELTA.T is a
positive value smaller than the predetermined determination value
or is a negative value, it is determined that an indoor unit 2
currently in a stopped state or no indoor unit 2 is connected to
the branch port 6 at which the aforementioned temperature
difference .DELTA.T is detected.
[0125] In this case, because a temperature difference .DELTA.Ta of
the indoor unit 2a operating in the heating mode is larger than the
predetermined value, the relay unit 3 determines that the indoor
unit 2a is connected to the branch port 6a.
[0126] Accordingly, the relay unit 3 can determine which one of the
branch ports 6 is connected to an indoor unit 2 currently in
operation.
[0127] If none of the temperature differences .DELTA.T is larger
than the predetermined value and the relay unit 3 cannot determine
a branch port 6 to which an indoor unit 2 currently performing
heating is connected after a specific time period, the relay unit 3
determines there is a setting error.
[0128] Subsequently, the relay unit 3 proceeds to step 108.
[0129] In step 108, the relay unit 3 transmits a stop command to
the indoor unit 2a in operation via the transmission line 71a so as
to stop the operation of the indoor unit 2a. Subsequently, the
process proceeds to step 109.
[0130] In step 109, it is determined whether there are indoor units
2 to which an operation command has not been transmitted yet. If
yes, the process proceeds to step 104. If no, the process proceeds
to step 110.
[0131] In this case, since an operation command has not been
transmitted to the indoor units 2b to 2d yet, the process proceeds
to step 104, and the same process is repeated.
[0132] Accordingly, the relay unit 3 makes all of the connected
indoor units 2 operate on a one-by-one basis and performs the
connected-branch-port determination process for identifying which
indoor unit 2 is connected to each branch port 6 on the basis of
the temperature difference .DELTA.T at that time.
[0133] When the determination process is completed for all of the
indoor units 2, the relay unit 3 proceeds to step 110.
[0134] In step 110, the relay unit 3 stops the heating only
operation mode and proceeds to step 111.
[0135] In step 111, a stop command is transmitted to the heat
source device 1, and the process proceeds to step 112.
[0136] In step 112, if a setting error is detected during the
determination process in step 107, the process proceeds to step
113. If a setting error is not detected, the process ends.
[0137] In this case, the term "setting error" refers to a case
where, for example, a connector that connects a wire extending from
a temperature sensor to a substrate is not connected or is
improperly connected, a connector that connects a wire extending
from an actuator, such as a flow control valve, to a substrate is
not connected or is improperly connected, or a normal temperature
change cannot be detected during a failure in an input-output
circuit.
[0138] In step 113, an abnormal-state notification process is
performed by, for example, displaying an abnormal state on display
means provided in a remote controller or the like or turning on an
error lamp provided in the heat source device 1. Subsequently, the
process ends.
[0139] Although the process of automatic determination of connected
branch ports shown in FIG. 3 is performed in the heating only
operation mode, the process can be performed similarly in the
cooling only operation mode. For example, hot water may be supplied
to an indoor unit 2 and may exchange heat with the cooling load in
the heating only operation mode during wintertime, and cold water
may be supplied to an indoor unit 2 and may exchange heat with the
heating load in the cooling only operation mode during summertime.
By identifying each branch port based on the temperature difference
.DELTA.T, the process of automatic determination of connected
branch ports can be performed year-round.
[0140] Accordingly, in Embodiment 1, the indoor units 2 are made to
operate on a one-by-one basis, and it is identified which indoor
unit 2 is connected to each branch port 6 on the basis of the
temperature difference .DELTA.T between the inlet temperature and
the outlet temperature of the branch port 6 at that time.
[0141] Therefore, it is not necessary to set connected branch ports
by using setting means, such as a DIP switch, in the indoor units 2
or the relay unit 3, so that the need for such setting means is
eliminated, whereby the component cost can be reduced. In addition,
the troublesome task involved in the setting process is not
necessary, thereby achieving enhanced user-friendliness.
[0142] Because the process of automatic determination of connected
branch ports is performed based on the detection values of the
third temperature sensors 33a to 33d and the fourth temperature
sensors 34a to 34d provided in the relay unit 3, it is not
necessary to transmit temperature data between the relay unit 3 and
the indoor units 2. Therefore, limitations with respect to the
communication of the indoor units 2 that can be connected to the
relay unit 3 can be reduced.
[0143] Furthermore, the interface between the relay unit 3 and each
indoor unit 2 can be controlled based on simple transmission of
information, which only includes the operation/stop commands, the
operating/stopped states, and the heating/cooling modes.
[0144] Thus, the interface between the relay unit 3 and each indoor
unit 2 can be achieved by inexpensive transmission means.
[0145] Moreover, other manufacturers' products, such as fan coil
units, can be readily connected.
[0146] With regard to the communication between the relay-unit
controller 63b and each indoor-unit controller 62, information can
be exchanged therebetween by input and output of binary signals
(on/off signals). Therefore, as compared with the configuration of
the related art shown in FIG. 8, the need for performing
digital-signal conversion during a transmission process and a
reception analysis process during reception can be eliminated.
Consequently, the program of the microcomputer 300a in the
relay-unit controller 63b is simplified, thereby reducing
limitations with respect to connectable indoor units 2.
Furthermore, the input-output circuits 302 and 303 can be achieved
with a simple configuration at a lower cost. Moreover, the
indoor-unit controllers 62 can also be achieved at a lower cost
since microcomputers are not used therein.
[0147] Because a setting error can be detected during the automatic
determination process, a determination error can be prevented in
advance. Moreover, improper connections, connection leak, and
defects in the connectors on the substrates in the relay-unit
controller 63b and the indoor-unit controllers 62 can be detected
at an early stage.
Embodiment 2
[0148] In Embodiment 2 described below, the time required for the
process of automatic determination of connected branch ports of the
indoor units 2 is shortened.
[0149] The process of automatic determination of connected branch
ports is desirably performed within a shorter period of time.
[0150] In Embodiment 2, a refrigerating and air-conditioning
apparatus is obtained that can shorten the time required for the
automatic determination process, as compared with the case where
the determination process is performed by making the indoor units 2
operate on a one-by-one basis.
[0151] FIG. 4 is a schematic circuit diagram illustrating the
configuration of the refrigerating and air-conditioning apparatus
according to Embodiment 2 of the present invention.
[0152] The following description mainly relates to points different
from Embodiment 1. Components that are the same as those in
Embodiment 1 are given the same reference numerals.
[0153] As shown in FIG. 4, the indoor units 2 in Embodiment 2 are
each provided with a ninth temperature sensor 39 and a tenth
temperature sensor 40.
[0154] The four ninth temperature sensors 39 (ninth temperature
sensors 39a to 39d) are provided at the inlet side of the
heat-medium passages of the use-side heat exchangers 26, are
configured to detect the temperature of the heat medium flowing
into the use-side heat exchangers 26, and may be formed of
thermistors or the like. The number of ninth temperature sensors 39
provided corresponds to the number of (four, in this case) indoor
units 2 installed.
[0155] In line with the indoor units 2, the ninth temperature
sensor 39a, the ninth temperature sensor 39b, the ninth temperature
sensor 39c, and the ninth temperature sensor 39d are shown in that
order from the lower side of the drawing.
[0156] The four tenth temperature sensors 40 (tenth temperature
sensors 40a to 40d) are provided at the outlet side of the
heat-medium passages of the use-side heat exchangers 26, are
configured to detect the temperature of the heat medium flowing out
of the use-side heat exchangers 26, and may be formed of
thermistors or the like. The number of tenth temperature sensors 40
provided corresponds to the number of (four, in this case) indoor
units 2 installed. In line with the indoor units 2, the tenth
temperature sensor 40a, the tenth temperature sensor 40b, the tenth
temperature sensor 40c, and the tenth temperature sensor 40d are
shown in that order from the lower side of the drawing.
[0157] The number of connected heat source devices 1, indoor units
2, and relay units 3 is not limited to that shown in the
drawing.
[0158] Detection values of the ninth temperature sensors 39 and the
tenth temperature sensors 40 in the indoor units 2 are transmitted
to the relay-unit controller 63b from the indoor-unit controllers
62 via the transmission lines 71. For example, temperature data is
converted into a transmittable digital signal by signal processing
performed by a microcomputer provided in each indoor-unit
controller 62, and the digital signal is converted into a signal
waveform by a transmission circuit before being transmitted via the
corresponding transmission line 71.
[0159] The refrigerating and air-conditioning apparatus 100 having
the above configuration performs the process of automatic
determination of connected branch ports so as to identify which
indoor unit 2 is connected to which branch port 6 during trial
operation performed after installation of the apparatus.
[0160] Next, the operation of the process of automatic
determination of connected branch ports in Embodiment 2 will be
described.
Process of Automatic Determination of Connected Branch Ports
[0161] FIG. 5 is a flowchart illustrating the flow of the process
of automatic determination of connected branch ports of the indoor
units in the refrigerating and air-conditioning apparatus according
to Embodiment 2 of the present invention.
[0162] The refrigerating and air-conditioning apparatus 100
commences the automatic determination process when, for example,
the switch 64 provided in the relay unit 3 is operated.
[0163] In FIG. 5, step 201 to step 217 correspond to a process
performed by the relay unit 3.
[0164] In step 202, the relay unit 3 transmits a trial heating main
operation command to the heat source device 1 and proceeds to step
203.
[0165] In step 203, the heat source device 1 receives the trial
heating main operation command from the relay unit 3 and starts
operating in the heating main operation mode described above.
[0166] Furthermore, the relay unit 3 starts operating in the
heating main operation mode. In this case, all of the stop valves
24a to 24d are closed. Subsequently, the process proceeds to step
204.
[0167] In step 204, an operation command is transmitted to all of
the indoor units 2a to 2d so that all of the indoor units 2 begin
to operate. Subsequently, the process proceeds to step 205.
[0168] In step 205, hot water is supplied to the next branch port
6. In this case, the stop valve 24a corresponding to the branch
port 6a is opened so as to switch the flow switching valve 22a and
the flow switching valve 23a to the passage connected to the
intermediate heat exchanger 15a for heating. Thus, hot water is
supplied from the branch port 6a. Subsequently, the process
proceeds to step 206.
[0169] In step 206, it is determined whether there are branch ports
6 that are not supplied with hot water or cold water yet. If yes,
the process proceeds to step 207. If no, the process proceeds to
step 208. In this case, since the branch ports 6b to 6d are not
supplied with hot water or cold water yet, the process proceeds to
step 207.
[0170] In step 207, cold water is supplied to the next branch port
6. In this case, the stop valve 24b corresponding to the branch
port 6b is opened so as to switch the flow switching valve 22b and
the flow switching valve 23b to the passage connected to the
intermediate heat exchanger 15b for cooling. Thus, cold water is
supplied from the branch port 6b. Subsequently, the process
proceeds to step 208.
[0171] In step 208, after waiting for a predetermined time to
elapse, the process proceeds to step 209.
[0172] In step 209, current water-temperature data of all of the
indoor units 2a to 2d are acquired. In this case, temperatures T39a
to T39d of the four ninth temperature sensors 39a to 39d are
acquired. Subsequently, the process proceeds to step 210.
[0173] In step 210, the branch-port determination process is
performed. In this case, changes in the data of the temperatures
T39a to T39d of the four ninth temperature sensors 39a to 39d are
checked.
[0174] In the indoor unit 2a connected to the branch port 6a
supplying hot water thereto, the temperature T39a of the ninth
temperature sensor 39a is substantially equal to the temperature of
the hot water. In the indoor unit 2b connected to the branch port
6b supplying cold water thereto, the temperature T39b of the ninth
temperature sensor 39b is substantially equal to the temperature of
the cold water.
[0175] Accordingly, if a certain temperature T39 is a value close
to the temperature of the hot water, the relay unit 3 determines
that the branch port 6a is connected to the indoor unit 2 at which
the aforementioned temperature T39 is detected. For example, the
temperature of the hot water is detected by the first temperature
sensor 31a. The determination of whether or not a certain
temperature T39 is a value close to the temperature of the hot
water is performed by determining whether or not a temperature
difference between the temperature of the hot water and the
temperature T39 is within a predetermined temperature range.
[0176] If a certain temperature T39 is a value close to the
temperature of the cold water, the relay unit 3 determines that the
branch port 6b is connected to the indoor unit 2 at which the
aforementioned temperature T39 is detected. For example, the
temperature of the cold water is detected by the first temperature
sensor 31b. The determination of whether or not a certain
temperature T39 is a value close to the temperature of the cold
water is performed by determining whether or not a temperature
difference between the temperature of the cold water and the
temperature T39 is within a predetermined temperature range.
[0177] If neither of the above, the relay unit 3 determines that
the indoor unit 2 at which the aforementioned temperature T39 is
detected is connected to one of the remaining branch ports 6c and
6d or is not connected to any of the branch ports 6.
[0178] Accordingly, the relay unit 3 can determine the indoor units
2 connected to the branch port 6a supplying hot water and the
branch port 6b supplying cold water.
[0179] If, after a specific time period of operation, the relay
unit 3 cannot determine the indoor units 2 connected to the branch
port 6 supplying hot water and the branch port 6 supplying cold
water or cannot determine neither of the indoor units 2, the relay
unit 3 determines a setting error.
[0180] Subsequently, the relay unit 3 proceeds to step 211.
[0181] In step 211, the water supply to the branch ports supplying
hot water and cold water is stopped. Subsequently, the process
proceeds to step 212.
[0182] In step 212, it is determined whether there are branch ports
6 not supplied with hot water or cold water yet. If yes, the
process proceeds to step 205. If no, the process proceeds to step
213.
[0183] In this case, since the branch ports 6c and 6d are not
supplied with hot water or cold water yet, the process proceeds to
step 205, and the same process is repeated.
[0184] Accordingly, the relay unit 3 performs the determination
process for all of the branch ports 6 by determining the indoor
units 2 connected to the branch ports 6 simultaneously and on a
two-by-two basis.
[0185] When the last one of the branch ports 6 remains, hot water
is supplied to that branch port 6, and the determination process
for the indoor unit 2 connected to that branch port 6 is
performed.
[0186] When the determination process is completed for all of the
branch ports 6, the relay unit 3 proceeds to step 213.
[0187] In step 213, the relay unit 3 transmits a stop command to
all of the indoor units 2 and proceeds to step 214.
[0188] In step 214, the relay unit 3 stops the heating main
operation mode and proceeds to step 215.
[0189] In step 215, a stop command is transmitted to the heat
source device 1, and the process proceeds to step 216.
[0190] In step 216, if a setting error is detected during the
determination process in step 210, the process proceeds to step
217. If no setting error is detected, the process ends.
[0191] In this case, the term "setting error" refers to a case
where, for example, a connector that connects a wire extending from
a temperature sensor to a substrate is not connected or is
improperly connected, a connector that connects a wire extending
from an actuator, such as a flow control valve, to a substrate is
not connected or is improperly connected, or where a normal
temperature change cannot be detected during a failure in an
input-output circuit.
[0192] In step 217, an abnormal-state notification process is
performed by, for example, displaying an abnormal state on display
means provided in a remote controller or the like or turning on an
error lamp provided in the heat source device 1. Subsequently, the
process ends.
[0193] Accordingly, in Embodiment 2, hot water and cold water are
simultaneously supplied to two branch ports 6 so that two indoor
units 2 connected to these branch ports 6 are simultaneously
identified on the basis of the temperatures of the heat medium
flowing into the corresponding use-side heat exchangers 26.
[0194] Therefore, the time required for the automatic determination
process can be shortened, as compared with the case where the
branch ports 6 are determined on a one-by-one basis. Moreover, a
setting error can be detected during the automatic determination
process.
Embodiment 3
[0195] In Embodiment 3 described below, the time required for the
process of automatic determination of connected branch ports of the
indoor units 2 is shortened.
[0196] The process of automatic determination of connected branch
ports is desirably performed within a shorter period of time.
[0197] In Embodiment 3, a refrigerating and air-conditioning
apparatus is obtained that can shorten the time required for the
automatic determination process, as compared with the case where
the determination process is performed by making the indoor units 2
operate on a one-by-one basis.
[0198] FIG. 6 is a schematic circuit diagram illustrating the
configuration of the refrigerating and air-conditioning apparatus
according to Embodiment 3 of the present invention.
[0199] The following description mainly relates to points different
from Embodiment 1. Components that are the same as those in
Embodiment 1 are given the same reference numerals.
[0200] As shown in FIG. 6, the indoor units 2 in Embodiment 3 are
each provided with an eleventh temperature sensor 41 and a twelfth
temperature sensor 42.
[0201] The four eleventh temperature sensors 41 (eleventh
temperature sensors 41a to 41d) are provided near air inlets of the
indoor units 2, are configured to detect the temperature of indoor
air, and may be formed of thermistors or the like. The number of
eleventh temperature sensors 41 provided corresponds to the number
of (four, in this case) indoor units 2 installed. In line with the
indoor units 2, the eleventh temperature sensor 41a, the eleventh
temperature sensor 41b, the eleventh temperature sensor 41c, and
the eleventh temperature sensor 41d are shown in that order from
the lower side of the drawing.
[0202] The four twelfth temperature sensors 42 (twelfth temperature
sensors 42a to 42d) are provided near air outlets of the indoor
units 2, are configured to detect the temperature of discharged
air, and may be formed of thermistors or the like. The number of
twelfth temperature sensors 42 provided corresponds to the number
of (four, in this case) indoor units 2 installed. In line with the
indoor units 2, the twelfth temperature sensor 42a, the twelfth
temperature sensor 42b, the twelfth temperature sensor 42c, and the
twelfth temperature sensor 42d are shown in that order from the
lower side of the drawing.
[0203] The number of connected heat source devices 1, indoor units
2, and relay units 3 is not limited to that shown in the
drawing.
[0204] Detection values of the eleventh temperature sensors 41 and
the twelfth temperature sensors 42 in the indoor units 2 are
transmitted to the relay-unit controller 63b from the indoor-unit
controllers 62 via the transmission lines 71. For example,
temperature data is converted into a transmittable digital signal
by signal processing performed by a microcomputer provided in each
indoor-unit controller 62, and the digital signal is converted into
a signal waveform by a transmission circuit and transmitted via the
corresponding transmission line 71.
[0205] The refrigerating and air-conditioning apparatus 100 having
the above configuration performs the process of automatic
determination of connected branch ports so as to identify which
indoor unit 2 is connected to which branch port 6 during trial
operation performed after installation of the apparatus.
[0206] Next, the operation of the process of automatic
determination of connected branch ports in Embodiment 3 will be
described.
Process of Automatic Determination of Connected Branch Ports
[0207] FIG. 7 is a flowchart illustrating the flow of the process
of automatic determination of connected branch ports of the indoor
units in the refrigerating and air-conditioning apparatus according
to Embodiment 3 of the present invention.
[0208] The refrigerating and air-conditioning apparatus 100
commences the automatic determination process when, for example,
the switch 64 provided in the relay unit 3 is operated.
[0209] In FIG. 7, step 301 to step 315 correspond to a process
performed by the relay unit 3.
[0210] In step 302, the relay unit 3 transmits a trial heating main
operation command to the heat source device 1 and proceeds to step
303.
[0211] In step 203, when the heat source device 1 receives the
trial heating main operation command from the relay unit 3, it
starts operating in the heating main operation mode described
above.
[0212] Furthermore, the relay unit 3 starts operating in the
heating main operation mode. In this case, all of the stop valves
24a to 24d are opened. Subsequently, the process proceeds to step
304.
[0213] In step 304, an operation command is transmitted to all of
the indoor units 2a to 2d so that all of the indoor units 2 begin
to operate. Subsequently, the process proceeds to step 305.
[0214] In step 305, the amount of hot water to be supplied, the
amount of cold water to be supplied, and the flow rates thereof are
calculated for the individual branch ports 6.
[0215] First, hot water is supplied to the first half of the branch
ports 6, whereas cold water is supplied to the second half of the
branch ports 6. In this case, hot water is supplied to the branch
ports 6a and 6b, whereas cold water is supplied to the branch ports
6c and 6d.
[0216] If the number of branch ports 6 is an odd number N, hot
water is supplied to a first group of branch ports 6 defined by a
maximum integer (2/N) that does not exceed 2/N, whereas cold water
is supplied to the second remaining group.
[0217] Then, the flow rates are calculated with L as the number of
branch ports 6 in the first half and M as the number of branch
ports 6 in the second half.
[0218] The flow rate at an A-th (A=1 to L) branch port 6 in the
first half is defined as A/L.times.100%. The flow rate at a B-th
(B=1 to M) branch port 6 in the second half is defined as
B/L.times.100%.
[0219] In this case, the flow rate at the branch port 6a is 50%,
the flow rate at the branch port 6b is 100%, the flow rate at the
branch port 6c is 50%, and the flow rate at the branch port 6d is
100%.
[0220] When the calculation is completed, the process proceeds to
step 306.
[0221] In step 306, hot water or cold water is supplied to each
branch port 6 based on the calculation results obtained in step
305, and the flow rate at each branch port 6 is set.
[0222] In this case, the flow switching valve 22a and the flow
switching valve 23a corresponding to the branch port 6a are
switched to the passage connected to the intermediate heat
exchanger 15a for heating so that hot water is supplied from the
branch port 6a. Furthermore, the opening degree of the flow control
valve 25a is adjusted so that the flow rate at the branch port 6a
is set to 50%.
[0223] Furthermore, the flow switching valve 22b and the flow
switching valve 23b corresponding to the branch port 6b are
switched to the passage connected to the intermediate heat
exchanger 15a for heating so that hot water is supplied from the
branch port 6b. Moreover, the opening degree of the flow control
valve 25b is adjusted so that the flow rate at the branch port 6b
is set to 100%.
[0224] Furthermore, the flow switching valve 22c and the flow
switching valve 23c corresponding to the branch port 6c are
switched to the passage connected to the intermediate heat
exchanger 15b for cooling so that cold water is supplied from the
branch port 6b. Moreover, the opening degree of the flow control
valve 25c is adjusted so that the flow rate at the branch port 6c
is set to 50%.
[0225] Furthermore, the flow switching valve 22d and the flow
switching valve 23d corresponding to the branch port 6d are
switched to the passage connected to the intermediate heat
exchanger 15b for cooling so that cold water is supplied from the
branch port 6d. Moreover, the opening degree of the flow control
valve 25d is adjusted so that the flow rate at the branch port 6b
is set to 100%.
[0226] Subsequently, the process proceeds to step 307.
[0227] In step 307, after waiting for a predetermined time to
elapse, the process proceeds to step 308.
[0228] In step 308, current suction temperature data and current
discharge temperature data of all of the indoor units 2a to 2d are
acquired. In this case, temperatures T41a to T41d of the four
eleventh temperature sensors 41a to 41d and temperatures T42a to
T42d of the four twelfth temperature sensors 42a to 42d are
acquired. Subsequently, the process proceeds to step 309.
[0229] In step 309, the branch-port determination process is
performed. In this case, changes in the data of the temperatures
T41a to T41d of the four eleventh temperature sensors 41a to 41d
and the temperatures T42a to T42d of the four twelfth temperature
sensors 42a to 42d are checked.
[0230] If a temperature difference between the discharge
temperature and the suction temperature in each of the indoor units
2 is defined as .DELTA.Ti (i=a, b, c, or d), the following
expression stands:
temperature difference .DELTA.Ti=T42i-T41i(i=a,b,c,or d)
[0231] In the indoor unit 2a connected to the branch port 6a
supplying hot water thereto, the temperature difference .DELTA.Ta
is a positive value since heat is transferred from the hot water to
air at the use-side heat exchanger 26a of the indoor unit 2a.
Likewise, in the indoor unit 2b connected to the branch port 6b
supplying hot water thereto, the temperature difference .DELTA.Tb
is a positive value. Because the flow rate at the branch port 6a is
50% and the flow rate at the branch port 6b is 100%, the
temperature difference .DELTA.Tb is a value larger than the
temperature difference .DELTA.Ta.
[0232] In the indoor unit 2c connected to the branch port 6c
supplying cold water thereto, the temperature difference .DELTA.Tc
is a negative value since the cold water receives heat from air at
the use-side heat exchanger 26c of the indoor unit 2c. Likewise,
also in the indoor unit 2d connected to the branch port 6d
supplying cold water thereto, the temperature difference .DELTA.Td
is a negative value. Because the flow rate at the branch port 6c is
50% and the flow rate at the branch port 6d is 100%, the
temperature difference .DELTA.Td is a negative value whose absolute
value is larger than that of the temperature difference
.DELTA.Tc.
[0233] Accordingly, if a certain temperature difference .DELTA.T is
a positive value that is smaller than a predetermined determination
value, the relay unit 3 determines that the indoor unit 2a supplied
with hot water at a flow rate of 50% is connected to the branch
port 6 at which the aforementioned temperature difference .DELTA.T
is detected.
[0234] If a certain temperature difference .DELTA.T is a positive
value that is larger than the predetermined determination value, it
is determined that the indoor unit 2b supplied with hot water at a
flow rate of 100% is connected to the branch port 6 at which the
aforementioned temperature difference .DELTA.T is detected.
[0235] If a certain temperature difference .DELTA.T is a negative
value and the absolute value thereof is smaller than the
predetermined determination value, it is determined that the indoor
unit 2c supplied with cold water at a flow rate of 50% is connected
to the branch port 6 at which the aforementioned temperature
difference .DELTA.T is detected.
[0236] If a certain temperature difference .DELTA.T is a negative
value and the absolute value thereof is larger than the
predetermined determination value, it is determined that the indoor
unit 2d supplied with cold water at a flow rate of 100% is
connected to the branch port 6 at which the aforementioned
temperature difference .DELTA.T is detected.
[0237] Accordingly, the relay unit 3 can determine the indoor units
connected to the branch ports.
[0238] If there are differences in the sizes (heat exchanger
capacities) of the use-side heat exchangers 26a to 26d in the
indoor units 2a to 2d or differences in the amount of air from fans
provided in the indoor units 2, the values of the temperature
differences .DELTA.Ta to .DELTA.Td are affected by such
differences. Therefore, it is necessary to perform a correction
process based on such data.
[0239] If the relay unit 3 cannot determine the indoor units 2
connected to all of the branch ports 6 after a specific time period
of operation, the relay unit 3 determines there is a setting
error.
[0240] Subsequently, the relay unit 3 proceeds to step 310.
[0241] In step 310, the water supply to the branch ports supplying
hot water and cold water is stopped. Subsequently, the process
proceeds to step 311.
[0242] In step 311, the relay unit 3 transmits a stop command to
all of the indoor units 2 and proceeds to step 312.
[0243] In step 312, the relay unit 3 stops the heating main
operation mode and proceeds to step 313.
[0244] In step 313, a stop command is transmitted to the heat
source device 1, and the process proceeds to step 314.
[0245] In step 314, if a setting error is detected during the
determination process in step 309, the process proceeds to step
315. If a setting error is not detected, the process ends.
[0246] In this case, the term "setting error" refers to a case
where, for example, a connector that connects a wire extending from
a temperature sensor to a substrate is not connected or is
improperly connected, a connector that connects a wire extending
from an actuator, such as a flow control valve, to a substrate is
not connected or is improperly connected, or a normal temperature
change cannot be detected during to a failure in an input-output
circuit.
[0247] In step 315, an abnormal-state notification process is
performed by, for example, displaying an abnormal state on display
means provided in a remote controller or the like or turning on an
error lamp provided in the heat source device 1. Subsequently, the
process ends.
[0248] Accordingly, in Embodiment 3, hot water and cold water are
simultaneously supplied to the branch ports 6, and the flow rate at
each branch port 6 is adjusted, so that a plurality of indoor units
2 connected to the branch ports 6 are simultaneously identified on
the basis of the temperature differences between the discharge
temperatures and the suction temperatures in the indoor units
2.
[0249] Therefore, the time required for the automatic determination
process can be shortened, as compared with the case where the
branch ports 6 are determined on a one-by-one basis. Moreover, a
setting error can be detected during the automatic determination
process.
REFERENCE SIGNS LIST
[0250] 1 heat source device 2a indoor unit 2b indoor unit 2c indoor
unit 2d indoor unit 3 relay unit 3a first relay unit 3b second
relay unit 4 refrigerant pipe 5a refrigerant pipe 5b refrigerant
pipe 6a branch port 6b branch port 6c branch port 6d branch port 10
compressor 11 four-way valve 12 heat-source-side heat exchanger 14
gas-liquid separator 15a intermediate heat exchanger 15b
intermediate heat exchanger 16a expansion valve 16b expansion valve
16c expansion valve 16d expansion valve 16e expansion valve 17
accumulator 21a pump 21b pump 22a flow switching valve 22b flow
switching valve 22c flow switching valve 22d flow switching valve
23a flow switching valve 23b flow switching valve 23c flow
switching valve 23d flow switching valve 24a stop valve 24b stop
valve 24c stop valve 24d stop valve 25a flow control valve 25b flow
control valve 25c flow control valve 25d flow control valve 26a
use-side heat exchanger 26b use-side heat exchanger 26c use-side
heat exchanger 26d use-side heat exchanger 27a bypass pipe 27b
bypass pipe 27c bypass pipe 27d bypass pipe 31a first temperature
sensor 31b first temperature sensor 32a second temperature sensor
32b second temperature sensor 33a third temperature sensor 33b
third temperature sensor 33c third temperature sensor 33d third
temperature sensor 34a fourth temperature sensor 34b fourth
temperature sensor 34c fourth temperature sensor 34d fourth
temperature sensor 35 fifth temperature sensor 36 pressure sensor
37 sixth temperature sensor 38 seventh temperature sensor 39a ninth
temperature sensor 39b ninth temperature sensor 39c ninth
temperature sensor 39d ninth temperature sensor 40a tenth
temperature sensor 40b tenth temperature sensor 40c tenth
temperature sensor 40d tenth temperature sensor 41a eleventh
temperature sensor 41b eleventh temperature sensor 41c eleventh
temperature sensor 41d eleventh temperature sensor 42a twelfth
temperature sensor 42b twelfth temperature sensor 42c twelfth
temperature sensor 42d twelfth temperature sensor 61 controller 62a
indoor-unit controller 62b indoor-unit controller 62c indoor-unit
controller 62d indoor-unit controller 63a relay-unit controller 63b
relay-unit controller 64 switch 71a transmission line 71b
transmission line 71c transmission line 100 refrigerating and
air-conditioning apparatus 200 controller 200 control unit 201
input circuit 202 output circuit 203 output circuit 300 control
unit 300a microcomputer 301 output circuit 302 input-output circuit
302 input circuit 303 input circuit 304 input circuit
* * * * *