U.S. patent application number 12/811564 was filed with the patent office on 2010-11-11 for air conditioning and hot water supply complex system.
This patent application is currently assigned to MITSUBISHI ELECTRIC CORPORATION. Invention is credited to Satoshi Akagi, Junichi Kameyama, Kosuke Tanaka, Hironori Yabuuchi.
Application Number | 20100282434 12/811564 |
Document ID | / |
Family ID | 41134897 |
Filed Date | 2010-11-11 |
United States Patent
Application |
20100282434 |
Kind Code |
A1 |
Yabuuchi; Hironori ; et
al. |
November 11, 2010 |
AIR CONDITIONING AND HOT WATER SUPPLY COMPLEX SYSTEM
Abstract
There is provided an air conditioning and hot water supply
complex system that can simultaneously treat a cooling load, a
heating load and a high-temperature hot water supply load and
supply a stable heat source throughout the year. In the air
conditioning and hot water supply complex system 100, the outdoor
heat exchanger 103 is made up of a plurality of divided heat
exchangers 103a, solenoid valves 209 are provided to respective
refrigerant pipes connected to the respective divided heat
exchanger 103a, and the solenoid valves 209 are opened or closed to
control a flow rate of air conditioning refrigerant flowing into
the respective divided heat exchangers 103a to thereby adjust the
operation range of the air conditioning compressor 101.
Inventors: |
Yabuuchi; Hironori; (Tokyo,
JP) ; Kameyama; Junichi; (Tokyo, JP) ; Tanaka;
Kosuke; (Tokyo, JP) ; Akagi; Satoshi; (Tokyo,
JP) |
Correspondence
Address: |
BUCHANAN, INGERSOLL & ROONEY PC
POST OFFICE BOX 1404
ALEXANDRIA
VA
22313-1404
US
|
Assignee: |
MITSUBISHI ELECTRIC
CORPORATION
CHIYODA-KU, TOKYO
JP
|
Family ID: |
41134897 |
Appl. No.: |
12/811564 |
Filed: |
March 31, 2008 |
PCT Filed: |
March 31, 2008 |
PCT NO: |
PCT/JP2008/056285 |
371 Date: |
July 2, 2010 |
Current U.S.
Class: |
165/63 ;
62/238.7; 62/324.6 |
Current CPC
Class: |
F25B 2313/0272 20130101;
F25B 2400/23 20130101; F25B 2313/0252 20130101; F25B 49/027
20130101; F24D 11/0235 20130101; F25B 2700/1931 20130101; F25B
2339/047 20130101; F25B 2400/0403 20130101; F25B 47/022 20130101;
F25B 2313/02741 20130101; F25B 2400/13 20130101; F25B 2313/0253
20130101; F25B 2700/1933 20130101; F25B 13/00 20130101; F25B
2700/2106 20130101; F25B 29/003 20130101; F25B 7/00 20130101; F24D
2200/31 20130101; Y02B 10/70 20130101; F25B 2313/0231 20130101;
Y02B 30/52 20130101 |
Class at
Publication: |
165/63 ;
62/238.7; 62/324.6 |
International
Class: |
F25B 29/00 20060101
F25B029/00; F25B 27/00 20060101 F25B027/00; F25B 13/00 20060101
F25B013/00 |
Claims
1. An air conditioning and hot water supply complex system
comprising; a heat source unit having an air conditioning
compressor, a flow path switching means and an outdoor heat
exchanger, and a plurality of indoor heat exchangers connected by
two or more pipes, wherein a cooling and heating simultaneous
operation, in which part of the plurality of indoor heat exchangers
perform cooling and part of the same perform heating
simultaneously, is operable, a hot water supply heat source heat
exchanger and a hot water supply heat source throttle means
connected in series are connected to the indoor heat exchanger in
parallel and, a cooling operation, a heating operation and a hot
water supply operation are performed simultaneously or selectively
according to an air conditioning load and a hot water supply
load.
2. The air conditioning and hot water supply complex system of
claim 1, wherein the outdoor heat exchanger is made up of a
plurality of heat exchangers or divided into a plurality of heat
exchangers, and a refrigerant flow rate flowing into the respective
plurality of heat exchangers or plurality of divided heat
exchangers are controlled.
3. An air conditioning and hot water supply complex system
comprising: an air conditioning refrigerating cycle including a
first refrigerant circuit and circulating an air conditioning
refrigerant through the first refrigerant circuit, the first
refrigerant circuit being formed by connecting an air conditioning
compressor, a flow path switching means, an outdoor heat exchanger,
an indoor heat exchanger, and an air conditioning throttle means in
series, connecting a refrigerant-refrigerant heat exchanger and a
hot water supply heat source throttle means in series, and
connecting the refrigerant-refrigerant heat exchanger and the hot
water supply heat source throttle means to the indoor heat
exchanger and the air conditioning throttle means in parallel; a
hot water supply refrigerating cycle including a second refrigerant
circuit and circulating a hot water supply refrigerant through the
second refrigerant circuit, the second refrigerant circuit being
formed by connecting a hot water supply compressor, a heat
medium-refrigerant heat exchanger, a hot water supply throttle
means, and the refrigerant-refrigerant heat exchanger in series;
and a hot water supply load including a water circuit and
circulating hot water supply water through the water circuit, the
water circuit being formed by connecting a water circulating pump,
the heat medium-refrigerant heat exchanger, and a hot water storage
tank in series, wherein the air conditioning refrigerating cycle
and the hot water supply refrigerating cycle are cascade-connected
so that the air conditioning refrigerant and the hot water supply
refrigerant exchange heat in the refrigerant-refrigerant heat
exchanger, the hot water supply refrigerating cycle and the hot
water supply load are cascade-connected so that the hot water
supply refrigerant and the water exchange heat in the heat
medium-refrigerant heat exchanger, the outdoor heat exchanger is
made up of a plurality of heat exchangers or divided into a
plurality of heat exchangers, opening and closing valves are
provided to each of refrigerant pipes connected to the plurality of
heat exchangers or the plurality of divided heat exchangers, and
the opening and closing valves are opened or closed to control flow
rates of the air conditioning refrigerant flowing into the
respective heat exchangers to adjust an operation range of the air
conditioning compressor.
4. The air conditioning and hot water supply complex system of
claim 3, wherein, when pressure of the refrigerant sucked into the
air conditioning compressor is not lower than a preset acceptable
value, the opening and closing valves are controlled so that the
pressure of the refrigerant sucked into the air conditioning
compressor does not exceed the acceptable value.
5. The air conditioning and hot water supply complex system of
claim 3, wherein at least one of the refrigerant pipes is formed as
a bypass circuit bypassing the outdoor heat exchanger and is
provided with a bypass opening and closing valve, and the bypass
opening and closing valve is opened or closed to allow the air
conditioning refrigerant to flow into the bypass circuit to thereby
adjust the operation range of the air conditioning compressor.
6. The air conditioning and hot water supply complex system of
claim 3, wherein a hot water supply heat medium circulating cycle
including a heat medium circuit and circulating a heat medium for
warming through the heat medium circuit is provided between the hot
water supply refrigerating cycle and the hot water supply load, the
heat medium circuit being formed by connecting a heat medium
circulating pump, the heat medium-refrigerant heat exchanger, and a
heat medium-heat medium heat exchanger in series, the hot water
supply refrigerating cycle and the hot water supply heat medium
circulating cycle are cascade-connected so that the hot water
supply refrigerant and the heat medium exchange heat in the heat
medium-refrigerant heat exchanger, and, the hot water supply heat
medium circulating cycle and the hot water supply load are
cascade-connected so that the heat medium and the water exchange
heat in the heat medium-heat medium heat exchanger.
7. The air conditioning and hot water supply complex system of
claim 3, wherein a refrigerant having a critical temperature not
lower than 60.degree. C. is employed for the hot water supply
refrigerant.
8. The air conditioning and hot water supply complex system of
claim 4, wherein at least one of the refrigerant pipes is formed as
a bypass circuit bypassing the outdoor heat exchanger and is
provided with a bypass opening and closing valve, and the bypass
opening and closing valve is opened or closed to allow the air
conditioning refrigerant to flow into the bypass circuit to thereby
adjust the operation range of the air conditioning compressor.
9. The air conditioning and hot water supply complex system of
claim 4, wherein a hot water supply heat medium circulating cycle
including a heat medium circuit and circulating a heat medium for
warming through the heat medium circuit is provided between the hot
water supply refrigerating cycle and the hot water supply load, the
heat medium circuit being formed by connecting a heat medium
circulating pump, the heat medium-refrigerant heat exchanger, and a
heat medium-heat medium heat exchanger in series, the hot water
supply refrigerating cycle and the hot water supply heat medium
circulating cycle are cascade-connected so that the hot water
supply refrigerant and the heat medium exchange heat in the heat
medium-refrigerant heat exchanger, and, the hot water supply heat
medium circulating cycle and the hot water supply load are
cascade-connected so that the heat medium and the water exchange
heat in the heat medium-heat medium heat exchanger.
10. The air conditioning and hot water supply complex system of
claim 5, wherein a hot water supply heat medium circulating cycle
including a heat medium circuit and circulating a heat medium for
warming through the heat medium circuit is provided between the hot
water supply refrigerating cycle and the hot water supply load, the
heat medium circuit being formed by connecting a heat medium
circulating pump, the heat medium-refrigerant heat exchanger, and a
heat medium-heat medium heat exchanger in series, the hot water
supply refrigerating cycle and the hot water supply heat medium
circulating cycle are cascade-connected so that the hot water
supply refrigerant and the heat medium exchange heat in the heat
medium-refrigerant heat exchanger, and, the hot water supply heat
medium circulating cycle and the hot water supply load are
cascade-connected so that the heat medium and the water exchange
heat in the heat medium-heat medium heat exchanger.
11. The air conditioning and hot water supply complex system of
claim 4, wherein a refrigerant having a critical temperature not
lower than 60.degree. C. is employed for the hot water supply
refrigerant.
12. The air conditioning and hot water supply complex system of
claim 5, wherein a refrigerant having a critical temperature not
lower than 60.degree. C. is employed for the hot water supply
refrigerant.
13. The air conditioning and hot water supply complex system of
claim 6, wherein a refrigerant having a critical temperature not
lower than 60.degree. C. is employed for the hot water supply
refrigerant.
Description
TECHNICAL FIELD
[0001] The present invention relates to an air conditioning and hot
water supply complex system that is equipped with a heat pump cycle
and can provide a cooling load, a heating load, and a hot water
supply load simultaneously.
BACKGROUND ART
[0002] Conventionally, there are an air conditioning and hot water
supply complex system that can provide a cooling load, a heating
load, and a hot water supply load simultaneously by a consolidated
refrigerating cycle. Proposed as such a system is "a
multifunctional heat pump system including a compressor and made up
of a refrigerating circuit formed by connecting the compressor, an
outdoor heat exchanger, an indoor heat exchanger, a cold and heat
storage tank, and a hot water supply heat exchanger, in which a
flow of refrigerant is switched between the respective heat
exchangers to thereby form a refrigerating cycle capable of
performing a cooling and heating operation, a hot water supply
operation, a heat storage operation, a cold storage operation
separately and simultaneously" (see Patent Document 1, for
example).
[0003] There are also air conditioning and hot water supply complex
systems capable of simultaneously providing high-temperature hot
water supply and indoor air conditioning functions by a binary
refrigerating cycle. Proposed as such a system is "a heat pump hot
water supplier in which a first compressor, a refrigerant
distributing device, a first heat exchanger, a second heat
exchanger, a first throttle device, an outdoor heat exchanger, a
four-way valve, and the first compressor are connected in this
order, the refrigerant distributing device, the four-way valve, an
indoor heat exchanger, and a second throttle device are connected
in this order between the second heat exchanger and the first
throttle device, a low stage side refrigerant circuit through which
a first refrigerant flows, a second compressor, a condenser, a
third throttle device, the first heat exchanger, and the second
compressor are connected in this order, and a high stage side
refrigerant circuit through which a second refrigerant flows, the
second heat exchanger, the condenser are connected in this order,
and a hot water supply path through which supplied hot water flows
is provided" (see Patent Document 2, for example).
[0004] Patent Document 1: Japanese Patent Application Laid-Open No.
11-270920 (pages 3 to 4, FIG. 1)
[0005] Patent Document 2: Japanese Patent Application Laid-Open No.
4-263758 (pages 2 to 3, FIG. 1)
DISCLOSURE OF THE INVENTION
Problems to be Solved by the Invention
[0006] The multifunctional heat pump system described in Patent
Document 1 simultaneously provides the cooling load, the heating
load, and the hot water supply load by one refrigerating cycle,
i.e., a single refrigerating cycle. In this system, however, a
temperature in a radiating process for heating water and a
temperature in a radiating process for heating are substantially
the same. Therefore, it is impossible to provide for a
high-temperature hot water supply load during cooling operation and
it is impossible to supply stable heat throughout the year.
[0007] The heat pump hot water supplier described in Patent
Document 2 simultaneously provides the cooling load, the heating
load, and the hot water supply load by a binary refrigerating
cycle, i.e., two refrigerating cycles. In this system, however, the
refrigerant circuit for performing air conditioning and the
refrigerant circuit for performing hot water supply in an indoor
unit are treated in different ways and it is impossible to simply
add a hot water supply function in place of the indoor unit.
Therefore, it is not easy to introduce the system into an existing
air conditioner.
[0008] The present invention has been made to solve the above
problems and it is an object of the invention to provide an air
conditioning and hot water supply complex system capable of
simultaneously treating a cooling load, a heating load, and a
high-temperature hot water supply load and supplying a stable heat
source throughout the year.
Means for Solving the Problems
[0009] An air conditioning and hot water supply complex system
according to the present invention comprises:
[0010] a heat source unit having an air conditioning compressor, a
flow path switching means and an outdoor heat exchanger, and
[0011] a plurality of indoor heat exchangers connected by two or
more pipes,
[0012] wherein a simultaneous cooling and heating operation, in
which part of the plurality of indoor heat exchangers perform
cooling and part of the same perform heating simultaneously, is
operable,
[0013] a hot water supply heat source heat exchanger and a hot
water supply heat source throttle means connected in series are
connected to the indoor heat exchanger in parallel and,
[0014] a cooling operation, a heating operation and a hot water
supply operation are performed simultaneously or selectively
according to an air conditioning load and a hot water supply
load.
[0015] An air conditioning and hot water supply complex system
according to the present invention comprises:
[0016] an air conditioning refrigerating cycle including a first
refrigerant circuit and circulating an air conditioning refrigerant
through the first refrigerant circuit, the first refrigerant
circuit being formed by connecting an air conditioning compressor,
a flow path switching means, an outdoor heat exchanger, an indoor
heat exchanger, and an air conditioning throttle means in series,
connecting a refrigerant-refrigerant heat exchanger and a hot water
supply heat source throttle means in series, and connecting the
refrigerant-refrigerant heat exchanger and the hot water supply
heat source throttle means to the indoor heat exchanger and the air
conditioning throttle means in parallel;
[0017] a hot water supply refrigerating cycle including a second
refrigerant circuit and circulating a hot water supply refrigerant
through the second refrigerant circuit, the second refrigerant
circuit being formed by connecting a hot water supply compressor, a
heat medium-refrigerant heat exchanger, a hot water supply throttle
means, and the refrigerant-refrigerant heat exchanger in series;
and
[0018] a hot water supply load including a water circuit and
circulating hot water supply water through the water circuit, the
water circuit being formed by connecting a water circulating pump,
the heat medium-refrigerant heat exchanger, and a hot water storage
tank in series,
[0019] wherein the air conditioning refrigerating cycle and the hot
water supply refrigerating cycle are cascade-connected so that the
air conditioning refrigerant and the hot water supply refrigerant
exchange heat in the refrigerant-refrigerant heat exchanger,
[0020] the hot water supply refrigerating cycle and the hot water
supply load are cascade-connected so that the hot water supply
refrigerant and the water exchange heat in the heat
medium-refrigerant heat exchanger,
[0021] the outdoor heat exchanger is made up of a plurality of heat
exchangers or divided into a plurality of heat exchangers,
[0022] opening and closing valves are provided to each of
refrigerant pipes connected to the plurality of heat exchanges or
the plurality of divided heat exchangers, and
[0023] the opening and closing valves are opened or closed to
control flow rates of the air conditioning refrigerant flowing into
the respective heat exchangers to adjust an operation range of the
air conditioning compressor.
EFFECTS OF THE INVENTION
[0024] According to the air conditioning and hot water supply
complex system of the invention, it is possible to simultaneously
or selectively perform the cooling operation, the heating
operation, and the hot water supply operation according to the air
conditioning load and the hot water supply load without forming a
complicated circuit.
[0025] According to the air conditioning and hot water supply
complex system of the present invention, flow rates of the air
conditioning refrigerant flowing into the respective plurality of
heat exchangers or plurality of divided heat exchangers are
controlled to adjust the operation range of the air conditioning
compressor. Therefore, it is possible to supply the stable
high-temperature hot water supply load throughout the year without
forming complicated circuits.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a refrigerant circuit diagram showing a
refrigerant circuit configuration of an air conditioning and hot
water supply complex system according to a first embodiment.
[0027] FIG. 2 is a schematic circuit block diagram for explaining
another example of a hot water supply load.
[0028] FIG. 3 is an explanatory diagram for explaining an example
of a structure of an outdoor heat exchanger.
[0029] FIG. 4 is a flowchart showing a flow of processing in
adjusting an operation range of an air conditioning compressor.
[0030] FIGS. 5(a) and 5(b) are explanatory diagrams for explaining
a hot water supply refrigerating cycle according to a second
embodiment.
[0031] FIG. 6 is a flowchart showing a flow of processing in
opening and closing a bypass solenoid valve.
[0032] FIGS. 7(a) and 7(b) are explanatory diagrams for explaining
a stored hot water circulating pipe according to a third
embodiment.
[0033] FIG. 8 is a schematic diagram for explaining height of a
trap.
EXPLANATION OF REFERENCE NUMERALS
[0034] 1 air conditioning refrigerating cycle, 2 hot water supply
refrigerating cycle, 2a hot water supply refrigerating cycle, 3 hot
water supply load, 4 hot water supply water circulating cycle 4, 21
hot water supply compressor, 22 hot water supply throttle means, 31
water circulating pump, 31a heat medium circulating pump, 32 hot
water storage tank, 41 refrigerant-refrigerant heat exchanger, 45
refrigerant pipe, 45a bypass pipe, 51 heat medium-refrigerant heat
exchanger, 51a heat medium-refrigerant heat exchanger, 100 air
conditioning and hot water supply complex system, 101 air
conditioning compressor, 102 four-way valve, 103 outdoor heat
exchanger, 103a divided heat exchanger, 104 accumulator, 105a check
valve, 105b check valve, 105c check valve, 105d check valve, 106
high pressure side connecting pipe, 107 low pressure side
connecting pipe, 108 gas-liquid separator, 109 distributing
section, 109a valve means, 109b valve means, 110 distributing
section, 110a check valve, 110b check valve, 111 internal heat
exchanger, 112 first repeater throttle means, 113 internal heat
exchanger, 114 second repeater throttle means, 115 meeting portion,
116 meeting portion, 116a meeting portion, 117 air conditioning
throttle means, 118 indoor heat exchanger, 119 hot water supply
heat source throttle means, 130 connecting pipe, 131 connecting
pipe, 132 connecting pipe, 133 connecting pipe, 133a connecting
pipe, 133b connecting pipe, 134 connecting pipe, 134a connecting
pipe, 134b connecting pipe, 135 connecting pipe, 135a connecting
pipe, 135b connecting pipe, 136 connecting pipe, 136a connecting
pipe, 136b connecting pipe, 201 water-water heat exchanger, 202
circulating water pipe, 203 stored hot water circulating pipe, 203a
stored hot water circulating pipe, 209 solenoid valve (opening and
closing valve), 209a solenoid valve (bypass opening and closing
valve), 210 trap, 300 bypass circuit, 309 bypass solenoid valve, A
heat source unit, B cooling indoor unit, C heating indoor unit, D
hot water supply heat source circuit, E repeater, a connection, b
connection, c connection, d connection
BEST MODES FOR CARRYING OUT THE INVENTION
[0035] Embodiments of the present invention will be described below
based on the drawings.
First Embodiment
[0036] FIG. 1 is a refrigerant circuit diagram showing a
refrigerant circuit configuration of an air conditioning and hot
water supply complex system 100 (and especially a refrigerant
circuit configuration in heating-based operation) according to a
first embodiment of the invention. Based on FIG. 1, the refrigerant
circuit configuration of the air conditioning and hot water supply
complex system 100 and especially the refrigerant circuit
configuration in the heating-based operation will be described. The
air conditioning and hot water supply complex system 100 is
installed in a building, an apartment house, or the like and
capable of simultaneously supplying a cooling load, a heating load,
and a hot water supply load by utilizing a refrigerating cycle
(heat pump cycle) circulating a refrigerant (air conditioning
refrigerant). In the following drawings including FIG. 1,
relationships between dimensions of respective component members
may be different from actual ones.
[0037] The air conditioning and hot water supply complex system 100
according to the first embodiment is made up of an air conditioning
refrigerating cycle 1, a hot water supply refrigerating cycle 2,
and a hot water supply load 3. Heat exchange is carried out by a
refrigerant-refrigerant heat exchanger 41 between the air
conditioning refrigerating cycle 1 and the hot water supply
refrigerating cycle 2 and by a heat medium-refrigerant heat
exchanger 51 between the hot water supply refrigerating cycle 2 and
the hot water supply load 3 so that their refrigerant and water do
not mix with each other. FIG. 1 shows a state (referred to as the
heating-based operation for the sake of convenience) of the air
conditioning refrigerating cycle 1, in which a load for a cooling
indoor unit B is smaller than a total load for a heating indoor
unit C and a hot water supply heat source circuit D and an outdoor
heat exchanger 103 functions as an evaporator.
[Air Conditioning Refrigerating Cycle 1]
[0038] The air conditioning refrigerating cycle 1 is made up of a
heat source unit A, a cooling indoor unit B for handling the
cooling load, the heating indoor unit C for handling the heating
load, the hot water supply heat source circuit D functioning as a
heat source of the hot water supply refrigerating cycle 2, and a
repeater E. Out of them, the cooling indoor unit B, the heating
indoor unit C, and the hot water supply heat source circuit D are
connected and mounted in parallel to the heat source unit A. The
repeater E installed between the heat source unit A, and the
cooling indoor unit B, the heating indoor unit C, and the hot water
supply heat source circuit D switches a flow of the refrigerant to
thereby cause the cooling indoor unit B, the heating indoor unit C,
and the hot water supply heat source circuit D to perform their
functions.
[Heat Source Unit A]
[0039] The heat source unit A is made up of an air conditioning
compressor 101, a four-way valve 102 as a flow path switching
means, the outdoor heat exchanger 103, and an accumulator 104
connected in series. The heat source unit A has a function of
supplying cold to the cooling indoor unit B, the heating indoor
unit C, and the hot water supply heat source circuit D. It is
preferable to provide, in a vicinity of the outdoor heat exchanger
103, an air blower such as a fan for supplying air to the outdoor
heat exchanger 103. In the heat source unit A, a high pressure side
connecting pipe 106 between the outdoor heat exchanger 103 and the
repeater E is provided with a check valve 105a for allowing a flow
of the air conditioning refrigerant only in a predetermined
direction (the direction from the heat source unit A to the
repeater E) and a low pressure side connecting pipe 107 between the
four-way valve 102 and the repeater E is provided with a check
valve 105b for allowing a flow of the air conditioning refrigerant
only in a predetermined direction (the direction from the repeater
E to the heat source unit A), respectively.
[0040] The high pressure side connecting pipe 106 and the low
pressure side connecting pipe 107 are connected by a first
connecting pipe 130 connecting an upstream side of the check valve
105a and an upstream side of the check valve 105b and a second
connecting pipe 131 connecting a downstream side of the check valve
105a and a downstream side of the check valve 105b. In other words,
a connection portion a between the high pressure side connecting
pipe 106 and the first connecting pipe 130 is on an upstream side
of a connection b between the high pressure side connecting pipe
106 and the second connecting pipe 131 with the check valve 105a
interposed therebetween. A connection portion c between the low
pressure side connecting pipe 107 and the first connecting pipe 130
is on an upstream side of a connection d between the low pressure
side connecting pipe 107 and the second connecting pipe 131 with
the check valve 105b interposed therebetween.
[0041] The first connecting pipe 130 is provided with a check valve
105c for allowing circulation of the air conditioning refrigerant
only in a direction from the low pressure side connecting pipe 107
to the high pressure side connecting pipe 106. The second
connecting pipe 131 is also provided with a check valve 105d for
allowing circulation of the air conditioning refrigerant only in a
direction from the low pressure side connecting pipe 107 to the
high pressure side connecting pipe 106. Because FIG. 1 shows the
refrigerant circuit configuration in the heating-based operation,
the check valve 105a and the check valve 105b are in closed states
(shown with black symbols) and the check valve 105b and the check
valve 105c are in open states (shown with white symbols).
[0042] The air conditioning compressor 101 draws in the air
conditioning refrigerant and compresses it to bring it into a
high-temperature and high-pressure state. The four-way valve 102
switches the flow of the air conditioning refrigerant. The outdoor
heat exchanger 103 functions as an evaporator or a heat radiator
(condenser) and carries out heat exchange between the air supplied
from the air blower (not shown) and the air conditioning
refrigerant to turn the air conditioning refrigerant into
evaporating gas or condensate liquid. The accumulator 104 is
disposed between the four-way valve 102 and the air conditioning
compressor 101 to store surplus air conditioning refrigerant in the
heating-based operation. The accumulator 104 may be a vessel that
can store the surplus air conditioning refrigerant.
[Cooling Indoor Unit B and Heating Indoor Unit C]
[0043] To each of the cooling indoor unit B and the heating indoor
unit C, an air conditioning throttle means 117 and an indoor heat
exchangers 118 are connected in series and mounted. In the shown
example, the two air conditioning throttle means 117 and the two
indoor heat exchangers 118 are mounted in parallel in each of the
cooling indoor unit B and the heating indoor unit C. The cooling
indoor unit B receives supply of the cold from the heat source unit
A and handles the cooling load and the heating indoor unit C
receives supply of the cold from the heat source unit A and handles
the heating load.
[0044] In other words, the first embodiment shows a state in which
the repeater E determines that the cooling indoor unit B handles
the cooling load and that the heating indoor unit C handles the
heating load. It is preferable to provide, in a vicinity of the
indoor heat exchangers 118, an air blower such as a fan for
supplying air to the indoor heat exchangers 118. For the sake of
convenience, connecting pipes from the repeater E and connected to
the indoor heat exchanger 118 are referred to as connecting pipes
133 and connecting pipes from the repeater E and connected to the
air conditioning throttle means 117 are referred to as connecting
pipes 134.
[0045] The air conditioning throttle means 117 function as
decompression valves and expansion valves to decompress and expand
the air conditioning refrigerant. Each of the air conditioning
throttle means 117 may be made up of a means an opening degree of
which can be variably controlled, e.g., a precision flow rate
control means formed of an electronic expansion valve and an
inexpensive refrigerant flow rate adjusting means such as a
capillary. The indoor heat exchanger 118 function as heat radiators
(condensers) and evaporators to carry out heat exchange between the
air supplied from the air blower (not shown) and the air
conditioning refrigerant to turn the air conditioning refrigerant
into condensate liquid or evaporating gas. The air conditioning
throttle means 117 and the indoor heat exchanger 118 are connected
in series.
[Hot Water Supply Heat Source Circuit D]
[0046] The hot water supply heat source circuit D is formed by
connecting a hot water supply heat source throttle means 119 and
the refrigerant-refrigerant heat exchanger 41 in series and has a
function of supplying the cold from the heat source unit A to the
hot water supply refrigerating cycle 2 via the
refrigerant-refrigerant heat exchanger 41. In other words, the air
conditioning refrigerating cycle 1 and the hot water supply
refrigerating cycle 2 are cascade-connected by the
refrigerant-refrigerant heat exchanger 41. For the sake of
convenience, a connecting pipe from the repeater E and connected to
the refrigerant-refrigerant heat exchanger 41 is referred to as a
connecting pipe 135 and a connecting pipe from the repeater E and
connected to the hot water supply heat source throttle means 119 is
referred to as a connecting pipe 136.
[0047] The hot water supply heat source throttle means 119
functions as a decompression valve and an expansion valve similarly
to the air conditioning throttle means 117 and decompresses and
expands the air conditioning refrigerant. The hot water supply heat
source throttle means 119 may be made up of a means an opening
degree of which can be variably controlled, e.g., a precision flow
rate control means formed of an electronic expansion valve and an
inexpensive refrigerant flow rate adjusting means such as a
capillary. The refrigerant-refrigerant heat exchanger 41 functions
as the heat radiator (condenser) and the evaporator and carries out
heat exchange between the hot water supply refrigerant circulating
in the refrigerating cycle of the hot water supply refrigerating
cycle 2 and the air conditioning refrigerant circulating in the
refrigerating cycle of the air conditioning refrigerating cycle
1.
[Repeater E]
[0048] The repeater E has a function of connecting each of the
cooling indoor unit B, the heating indoor unit C, and the hot water
supply heat source circuit D to the heat source unit A and a
function of determining whether the indoor heat exchangers 118
serve as the heat radiators or the evaporators and whether the
refrigerant-refrigerant heat exchanger 41 serves as a water cooler
or a hot water supplier by opening or closing either one of a valve
means 109a or a valve means 109b of a first distributing section
109. The repeater E is made up of a gas-liquid separator 108, a
first distributing section 109, a second distributing section 110,
a first internal heat exchanger 111, a first repeater throttle
means 112, a second internal heat exchanger 113, and a second
repeater throttle means 114.
[0049] In the first distributing section 109, the connecting pipes
133 and the connecting pipe 135 are divided into two pipes, ones of
which (connecting pipes 133b and a connecting pipe 135b) are
connected to the low pressure side connecting pipe 107 and the
others (connecting pipes 133a and a connecting pipe 135a) are
connected to a connecting pipe (referred to as a connecting pipe
132) connected to the gas-liquid separator 108. In the first
distributing section 109, the connecting pipes 133a and the
connecting pipe 135a are provided with the valve means 109a that
are controlled to open or close to let or not to let the
refrigerant through and the connecting pipes 133b and the
connecting pipe 135b are provided with the valve means 109b that
are controlled to open or close to let or not to let the
refrigerant through. Open and closed states of the valve means 109a
and the valve means 109b are shown by white symbols (open states)
and black symbols (closed states).
[0050] In the second distributing section 110, the connecting pipes
134 and the connecting pipe 136 are divided into two pipes, ones of
which (connecting pipes 134a and a connecting pipe 136a) are
connected by a first meeting portion 115 and the others (connecting
pipes 134b and a connecting pipe 136b) are connected by a second
meeting portion 116. In the second distributing section 110, the
connecting pipes 134a and the connecting pipe 136a are provided
with check valves 110a for allowing flows of the refrigerant only
in one direction and the connecting pipes 134b and the connecting
pipe 136b are provided with check valves 110b for allowing flows of
the refrigerant only in one direction, respectively. Open and
closed states of the check valves 110a and the check valves 110b
are shown by white symbols (open states) and black symbols (closed
states).
[0051] The first meeting portion 115 extends from the second
distributing section 110 and is connected to the gas-liquid
separator 108 via the first repeater throttle means 112 and the
first internal heat exchanger 111. The second meeting portion 116
is divided into two between the second distributing section 110 and
the second internal heat exchanger 113, one of which is connected
to the first meeting portion 115 between the second distributing
section 110 and the first repeater throttle means 112 via the
second internal heat exchanger 113 and the other (the second
meeting portion 116a) is connected to the low pressure side
connecting pipe 107 via the second repeater throttle means 114, the
second internal heat exchanger 113, and the first internal heat
exchanger 111.
[0052] The gas-liquid separator 108 separates the air conditioning
refrigerant into a gas refrigerant and a liquid refrigerant and is
provided in the high pressure side connecting pipe 106. One end of
the gas-liquid separator 108 is connected to the valve means 109a
of the first distributing section 109 and the other end is
connected to the second distributing section 110 via the first
meeting portion 115. The first distributing section 109 has a
function of allowing the air conditioning refrigerant to flow into
the indoor heat exchangers 118 and the refrigerant-refrigerant heat
exchanger 41 as either the valve means 109a or the valve means 109b
are opened or closed. The second distributing section 110 has a
function of allowing flows of the air conditioning refrigerant in
one direction with the check valves 110a and the check valves
110b.
[0053] The first internal, heat exchanger 111 is provided to the
first meeting portion 115 between the gas-liquid separator 108 and
the first repeater throttle means 112 and carries out heat exchange
between the air conditioning refrigerant passing through the first
meeting portion 115 and the air conditioning refrigerant passing
through the second meeting portion 116a branching off the second
meeting portion 116. The first repeater throttle means 112 is
provided to the first meeting portion 115 between the first
internal heat exchanger 111 and the second distributing section 110
and decompresses and expands the air conditioning refrigerant. The
first repeater throttle means 112 may be made up of a means an
opening degree of which can be variably controlled, e.g., a
precision flow rate control means formed of an electronic expansion
valve and an inexpensive refrigerant flow rate adjusting means such
as a capillary.
[0054] The second internal heat exchanger 113 is provided to the
second meeting portion 116 and carries out heat exchange between
the air conditioning refrigerant passing through the second meeting
portion 116 and the air conditioning refrigerant passing through
the second meeting portion 116a branching off the second meeting
portion 116. The second repeater throttle means 114 is provided to
the second meeting portion 116 between the second internal heat
exchanger 113 and the second distributing section 110 and functions
as a decompression valve and an expansion valve to decompress and
expand the air conditioning refrigerant. Similarly to the first
repeater throttle means 112, the second repeater throttle means 114
may be made up of a means an opening degree of which can be
variably controlled, e.g., a precision flow rate control means
formed of an electronic expansion valve and an inexpensive
refrigerant flow rate adjusting means such as a capillary.
[0055] As described above, the air conditioning refrigerating cycle
1 is formed by connecting the air conditioning compressor 101, the
four-way valve 102, the indoor heat exchanger 118, the air
conditioning throttle means 117, and the outdoor heat exchanger 103
in series, connecting the air conditioning compressor 101, the
four-way valve 102, the refrigerant-refrigerant heat exchanger 41,
the hot water supply heat source throttle means 119, and the
outdoor heat exchanger 103 in series, connecting the indoor heat
exchanger 118 and the refrigerant-refrigerant heat exchanger 41 in
parallel through the repeater E to form the first refrigerant
circuit, and circulating the air conditioning refrigerant through
the first refrigerant circuit.
[0056] The air conditioning compressor 101 may be any type of
compressor that can compress the drawn-in refrigerant into a
high-pressure state. For example, various types such as
reciprocating, rotary, scroll, and screw types may be used to form
the air conditioning compressor 101. The air conditioning
compressor 101 may be formed as a type a rotation number of which
can be variably controlled by an inverter or as a type a rotation
of which is fixed. The kind of the refrigerant circulating through
the air conditioning refrigerating cycle 1 is not especially
limited. For example, any of a natural refrigerant such as carbon
dioxide (CO.sub.2), hydrocarbon, and helium, an alternative
refrigerant such as HFC410A, HFC407C, and HFC404A not including
chlorine, and a fluorocarbon refrigerant such as R22 and R134a used
for existing products may be used.
[0057] Here, operation of the heating-based operation of the air
conditioning refrigerating cycle 1 will be described.
[0058] First, the air conditioning refrigerant brought into the
high-temperature and high-pressure state by the air conditioning
compressor 101 is discharged from the air conditioning compressor
101, passes through the four-way valve 102 and the check valve
105c, is introduced into the high pressure side connecting pipe
106, and flows into the gas-liquid separator 108 of the repeater E
in a state of superheated gas. The air conditioning refrigerant
flowing into the gas-liquid separator 108 in the state of
superheated gas is distributed to circuits through the open valve
means 109a in the first distributing section 109. Here, the air
conditioning refrigerant in the state of the superheated gas flows
into the heating indoor unit C and the hot water supply heat source
circuit D.
[0059] Flows of the air conditioning refrigerant flowing into the
heating indoor unit C radiate heat (i.e., warms up indoor air) at
the indoor heat exchangers 118, are decompressed by the air
conditioning throttle means 117, and join at the first meeting
portion 115. The air conditioning refrigerant flowing into the hot
water supply heat source circuit D radiates heat (i.e., gives heat
to the hot water supply refrigerating cycle 2) at the
refrigerant-refrigerant heat exchanger 41, is decompressed by the
hot water supply heat source throttle means 119, and joins the air
conditioning refrigerant flowing out of the heating indoor unit C
at the first meeting portion 115. On the other hand, part of the
air conditioning refrigerant flowing into the gas-liquid separator
108 in the state of superheated gas, at the first internal heat
exchanger 111, with the air conditioning refrigerant expanded into
a low-temperature and low-pressure state by the second repeater
throttle means 114 to thereby obtain a supercooling degree.
[0060] Then, the air conditioning refrigerant passes through the
first repeater throttle means 112 and joins the air conditioning
refrigerant used for air conditioning (the air conditioning
refrigerant that has flowed into the heating indoor unit C and the
hot water supply heat source circuit D and radiated heat at the
indoor heat exchangers 118 and the refrigerant-refrigerant heat
exchanger 41) at the first meeting portion 115. The first repeater
throttle means 112 may be fully closed so that no air conditioning
refrigerant in the state of the superheated gas passes through the
first repeater throttle means 112. Then, in the second internal
heat exchanger 113, the air conditioning refrigerant exchanges heat
exchanges heat with the air conditioning refrigerant that has
expanded into the low-temperature and low-pressure state at the
second repeater throttle means 114 to thereby obtain a supercooling
degree. This air conditioning refrigerant is distributed to the
second meeting portion 116 and the second repeater throttle means
114.
[0061] The air conditioning refrigerant passing through the second
meeting portion 116 is distributed into the circuits where the
valve means 109b are open. Here, the air conditioning refrigerant
passing through the second meeting portion 116 flows into the
cooling indoor unit B. The flows of the air conditioning
refrigerant are expanded into low-temperature and low-pressure
states by the air conditioning throttle means 117, evaporate in the
indoor heat exchangers 118, pass through the valve means 109b, and
join in the low pressure side connecting pipe 107. On the other
hand, the air conditioning refrigerant that has passed through the
second repeater throttle means 114 exchanges heat in the second
internal heat exchanger 113 and the first internal heat exchanger
111 to evaporate and joins, in the low pressure side connecting
pipe 107, the air conditioning refrigerant flowing out of the
cooling indoor unit B. The air conditioning refrigerant joined in
the low pressure side connecting pipe 107 is introduced to the
outdoor heat exchanger 103 via the check valve 105d, evaporates
remaining liquid refrigerant depending on operating conditions,
passes through the four-way valve 102 and the accumulator 104, and
returns to the air conditioning compressor 101.
[Hot Water Supply Refrigerating Cycle 2]
[0062] The hot water supply refrigerating cycle 2 is made up of a
hot water supply compressor 21, the heat medium-refrigerant heat
exchanger 51, a hot water supply throttle means 22, and the
refrigerant-refrigerant heat exchanger 41. In other words, the hot
water supply refrigerating cycle 2 is formed by connecting the hot
water supply compressor 21, the heat medium-refrigerant heat
exchanger 51, the hot water supply throttle means 22, and the
refrigerant-refrigerant heat exchanger 41 in series by a
refrigerant pipe 45 to form a second refrigerant circuit and
circulating a hot water supply refrigerant through the second
refrigerant circuit. Operation of the hot water supply
refrigerating cycle 2 does not change depending on an operating
state of the air conditioning refrigerating cycle 1, i.e., whether
cooling-based operation or the heating-based operation is carried
out.
[0063] The hot water supply compressor 21 draws in the hot water
supply refrigerant and compresses the hot water supply refrigerant
to bring it into a high-temperature and high-pressure state. The
hot water supply compressor 21 may be of a type a rotation number
of which can be variably controlled by an inverter or a type a
rotation number of which is fixed. The hot water supply compressor
21 can be of any type if it can compress the drawn-in refrigerant
into the high-pressure state. Various types such as reciprocating,
rotary, scroll, and screw types may be used to form the hot water
supply compressor 21.
[0064] The heat medium-refrigerant heat exchanger 51 carries out
heat exchange between water (heat medium) circulating through the
hot water supply load 3 and the hot water supply refrigerant
circulating through the hot water supply refrigerating cycle 2. In
other words, the hot water supply refrigerating cycle 2 and the hot
water supply load 3 are cascade-connected by the heat
medium-refrigerant heat exchanger 51. The hot water supply throttle
means 22 functions as a decompression valve and an expansion valve
and decompresses and expands the hot water supply refrigerant. The
hot water supply throttle means 22 may be made up of a means an
opening degree of which can be variably controlled, e.g., a
precision flow rate control means formed of an electronic expansion
valve and an inexpensive refrigerant flow rate adjusting means such
as a capillary.
[0065] The refrigerant-refrigerant heat exchanger 41 carries out
heat exchange between the hot water supply refrigerant circulating
through the hot water supply refrigerating cycle 2 and the air
conditioning refrigerant circulating through the air conditioning
refrigerating cycle 1. The kind of the refrigerant circulating
through the hot water supply refrigerating cycle 2 is not
especially limited. For example, any of the natural refrigerant
such as carbon dioxide, hydrocarbon, and helium, the alternative
refrigerant such as HFC410A, HFC407C, and HFC404A not including
chlorine, and the fluorocarbon refrigerant such as R22 and R134a
used for existing products may be used.
[0066] Here, operation of the hot water supply refrigerating cycle
2 will be described.
[0067] First, the hot water supply refrigerant brought into the
high-temperature and high-pressure state by the hot water supply
compressor 21 is discharged from the hot water supply compressor 21
and flows into the heat medium-refrigerant heat exchanger 51. In
the heat medium-refrigerant heat exchanger 51, the flowing-in hot
water supply refrigerant heats water circulating through the hot
water supply load 3 to thereby radiate heat. The hot water supply
refrigerant is expanded by the hot water supply throttle means 22
to a temperature not higher than an exit temperature of the
refrigerant-refrigerant heat exchanger 41 in the hot water supply
heat source circuit D in the air conditioning refrigerating cycle
1. The expanded hot water supply refrigerant receives heat, in the
refrigerant-refrigerant heat exchanger 41, from the air
conditioning refrigerant flowing through the hot water supply heat
source circuit D forming the air conditioning refrigerating cycle
1, evaporates, and returns to the hot water supply compressor
21.
[Hot Water Supply Load 3]
[0068] The hot water supply load 3 is made up of a water
circulating pump 31, the heat medium-refrigerant heat exchanger 51,
and a hot water storage tank 32. In other words, the hot water
supply load 3 is formed by connecting the water circulating pump
31, the heat medium-refrigerant heat exchanger 51, and the hot
water storage tank 32 in series by a stored hot water circulating
pipe 203 to form a water circuit (heat medium circuit) and
circulating hot water supply water through the water circuit.
Operation of the hot water supply load 3 does not change depending
on the operating state of the air conditioning refrigerating cycle
1, i.e., whether the cooling-based operation or the heating-based
operation is carried out. The stored hot water circulating pipe 203
forming the water circuit is made up of a copper pipe, a stainless
pipe, a steel pipe, a vinyl chloride pipe, and the like.
[0069] The water circulating pump 31 draws in the water stored in
the hot water storage tank 32, pressurizes the water, and
circulates it through the hot water supply load 3 and may be of a
type a rotation number of which is controlled by an inverter, for
example. As described above, the heat medium-refrigerant heat
exchanger 51 carries out heat exchange between the water (heat
medium) circulating through the hot water supply load 3 and the hot
water supply refrigerant circulating through the hot water supply
refrigerating cycle 2. The hot water storage tank 32 is for storing
the water heated by the heat medium-refrigerant heat exchanger
51.
[0070] First, relatively low-temperature water stored in the hot
water storage tank 32 is pumped up from a bottom portion of the hot
water storage tank 32 and pressurized by the water circulating pump
31. The water pressurized by the water circulating pump 31 flows
into the heat medium-refrigerant heat exchanger 51 and receives
heat from the hot water supply refrigerant circulating through the
hot water supply refrigerating cycle 2 at the heat
medium-refrigerant heat exchanger 51. In other words, the water
that flowed into the heat medium-refrigerant heat exchanger 51 is
boiled by the hot water supply refrigerant circulating through the
hot water supply refrigerating cycle 2 and a temperature of the
water increases. Then, the boiled water returns to a relatively
high-temperature upper portion of the hot water storage tank 32 and
is stored in the hot water storage tank 32.
[0071] Because the air conditioning refrigerating cycle 1 and the
hot water supply refrigerating cycle 2 are formed as refrigerant
circuit configurations (the first refrigerant circuit forming the
air conditioning refrigerating cycle 1 and the second refrigerant
circuit forming the hot water supply refrigerating cycle 2)
independent of each other as described above, the same kind or
different kinds of refrigerant may be circulated through the
respective refrigerant circuits. In other words, the refrigerants
in the respective refrigerant circuits flow and exchange heat with
each other at the refrigerant-refrigerant heat exchanger 41 and the
heat medium-refrigerant heat exchanger 51 without mixing with each
other.
[0072] If a refrigerant having a low critical temperature is used
as the hot water supply refrigerant, the hot water supply
refrigerant in the heat radiating process at the heat
medium-refrigerant heat exchanger 51 is expected to come into a
supercritical state in supplying high-temperature hot water.
However, in general, if the refrigerant in the heat radiating
process is in the supercritical state, a COP changes a lot due to
changes in the heat radiator pressure and the heat radiator exit
temperature. Therefore, advanced control is required to carry out
operation for obtaining the high COP. On the other hand, in
general, the refrigerant having the low critical temperature has
higher saturation pressure for the same temperature and therefore
it is necessary to increase wall thickness of the pipe and the
compressor, which causes an increase in cost.
[0073] Considering that recommended temperature of water stored in
the hot water storage tank 32 for keeping away Legionella bacteria
and the like from developing is not lower than 60.degree. C., a
minimum target temperature of hot water supply is expected to be
60.degree. C. in many cases. With the above circumstances in view,
the refrigerant having the minimum critical temperature of
60.degree. C. is employed as the hot water supply refrigerant. If
such a refrigerant is employed as the hot water supply refrigerant
in the hot water supply refrigerating cycle 2, it is possible to
more stably obtain the higher COP at lower cost. If the refrigerant
is constantly used around the critical temperature, the inside of
the refrigerant circuit is expected to become high-temperature and
high pressure. Therefore, if a compressor of a type using a
high-pressure shell is employed as the hot water supply compressor
21, it is possible to achieve stable operation.
[0074] Although the surplus refrigerant is stored in the receiver
(accumulator 104) in the air conditioning refrigerating cycle 1 in
the shown example, it is not the absolute necessity. If the surplus
refrigerant is stored in the heat exchanger serving as the heat
radiator in the refrigerating cycle, the accumulator 104 may be
removed. Although two or more cooling indoor units B and the
heating indoor units C are connected in the example shown in FIG.
1, the numbers of units to be connected are not especially limited.
For example, it is essential only that one or more cooling indoor
units B without the heating indoor unit C or with one or more
heating indoor units C be connected. Capacities of the respective
indoor units forming the air conditioning refrigerating cycle 1 may
be the same or may vary from a large capacity to a small one.
[0075] As described above, the hot water supply load system is made
up of a binary cycle in the air conditioning and hot water supply
complex system 100 according to the first embodiment. Therefore, to
meet a high-temperature hot water supply demand (e.g., 80.degree.
C.), it is essential only that the temperature of the heat radiator
in the hot water supply refrigerating cycle 2 be high (e.g., the
condensation temperature of 85.degree. C.) and it is unnecessary to
increase the condensation temperature (e.g., 50.degree. C.) of the
heating indoor unit C as well when there is a heating load, which
conserves energy. If there is a demand for high-temperature hot
water supply during air conditioning cooling operation in summer, a
boiler or the like needs to be used to meet the demand in prior
art. However, heat that has been conventionally emitted into the
atmosphere can be recovered and used again to supply hot water,
which substantially increases the system COP and conserves
energy.
[0076] FIG. 2 is a schematic circuit block diagram for explaining
another example of the hot water supply load 3. Based on FIG. 2, an
example of an arrangement having another form of hot water supply
load 3 and heating circulating water will be described. As shown in
FIG. 2, between the hot water supply refrigerating cycle 2 and the
hot water supply load 3, a hot water supply water circulating cycle
(hot water supply heat medium circulating cycle) 4 is
cascade-connected through a heat medium-refrigerant heat exchanger
51 and a water-water heat exchanger (heat medium-heat medium heat
exchanger) 201. In the example shown in FIG. 1, water is directly
warmed by the heat medium-refrigerant heat exchanger 51 in the hot
water supply load 3 formed as a closed circuit. On the other hand,
in the example shown in FIG. 2, the hot water supply load 3 formed
as an open circuit has the hot water supply water circulating cycle
4 between the hot water supply refrigerating cycle 2 and itself and
water is indirectly warmed by the water-water heat exchanger
201.
[Hot Water Supply Water Circulating Cycle 4]
[0077] The hot water supply water circulating cycle 4 is made up of
a heat medium circulating pump 31a, the heat medium-refrigerant
heat exchanger 51, and the water-water heat exchanger 201. In other
words, the hot water supply water circulating cycle 4 is formed by
connecting the heat medium circulating pump 31a, the heat
medium-refrigerant heat exchanger 51, and the water-water heat
exchanger 201 in series by a circulating water pipe 202 to form a
water circuit (heat medium circuit) and circulating warming heat
medium (warming water) through the heat medium circuit (water
circuit). The circulating water pipe 202 forming the water circuit
is made up of a copper pipe, a stainless pipe, a steel pipe, a
vinyl chloride pipe, and the like.
[0078] The heat medium circulating pump 31a draws in water (heat
medium) passing through the circulating water pipe 202, pressurizes
the water, and circulates it through the hot water supply water
circulating cycle 4 and may be of a type a rotation number of which
is controlled by an inverter, for example. The heat
medium-refrigerant heat exchanger 51 carries out heat exchange
between the water circulating through the hot water supply water
circulating cycle 4 and the hot water supply refrigerant
circulating through the hot water supply refrigerating cycle 2. The
water-water heat exchanger 201 carries out heat exchange between
the water circulating through the hot water supply water
circulating cycle 4 and the water circulating through the hot water
supply load 3. Although the water is circulated through the hot
water supply water circulating cycle 4 in the example explained
here, other fluid such as brine (antifreeze liquid) may be
circulated as the heat medium.
[0079] First, the relatively low-temperature water stored in the
hot water storage tank 32 is pumped up from the bottom portion of
the hot water storage tank 32 and pressurized by the water
circulating pump 31. The water pressurized by the water circulating
pump 31 flows into the water-water heat exchanger 201 and receives,
at the water-water heat exchanger 201, heat from the water
circulating through the hot water supply water circulating cycle 4.
In other words, the water that flowed into the water-water heat
exchanger 201 is boiled by the water circulating through the hot
water supply water circulating cycle 4 and a temperature of the
water increases. Then, the boiled water returns to a relatively
high-temperature upper portion of the hot water storage tank 32 and
is stored in the hot water storage tank 32. In other words, heat
from the hot water supply refrigerating cycle 2 is transmitted to
the hot water supply water circulating cycle 4 at the heat
medium-refrigerant heat exchanger 51 and to the hot water supply
load 3 at the water-water heat exchanger 201, respectively.
[0080] FIG. 3 is an explanatory diagram for explaining an example
of a structure of an outdoor heat exchanger 103. Based on FIG. 3,
the outdoor heat exchanger 103 that can perform heating operation
throughout the year will be described. If the air conditioning and
hot water supply complex system 100 is used only for normal air
conditioning, heating operation is generally carried out at an
outside-air wet-bulb temperature not higher than 15.degree. C. To
carry out the hot water supply operation, however, it is necessary
to carry out the hot water supply operation irrespective of the
outside-air temperature. Therefore, FIG. 3 shows an example in
which the outdoor heat exchanger 103 has a divided structure
having, inside itself, a plurality of heat exchangers (hereafter
referred to as divided heat exchangers 103a). The outdoor heat
exchanger 103 may be a divided structure formed by combining four
heat exchangers or may be a divided structure formed by dividing
one heat exchanger into four.
[0081] As shown in FIG. 3, the high pressure side connecting pipe
106 is divided into a plurality of pipes and connected to the
respective divided heat exchangers 103a forming the outdoor heat
exchanger 103. The respective divided pipes of the high pressure
side connecting pipe 106 are provided with solenoid valves 209 that
are opening and closing valves controlled to open or close to allow
or not allow passage of the refrigerant. One of the plurality of
divided pipes of the high pressure side connecting pipe 106 is
formed as a bypass circuit 300 bypassing the divided heat
exchangers 103a. The bypass circuit 300 is also provided with the
solenoid valve 209a that is a bypass opening and closing valve. In
other words, in the outdoor heat exchanger 103 forming the air
conditioning refrigerating cycle 1, an amount of incoming
refrigerant can be adjusted by controlling opening and closing of
the solenoid valve 209 and the solenoid valve 209a and a capacity
of the heat exchanger can be divided.
[0082] If the outside-air wet-bulb temperature increases, i.e., if
a suction temperature of the air conditioning compressor 101 is
expected to increase beyond an operation range (15.degree. C. at
the maximum, in general) it is preferable to reduce heat exchanger
performance of the outdoor heat exchanger 103. Therefore, in the
air conditioning and hot water supply complex system 100, all or
part of the solenoid valves 209 are controlled to close to
interrupt the refrigerant flowing into the outdoor heat exchanger
103 so that the operation range of the air conditioning compressor
101 is not exceeded. In other words, by determining the number of
divided heat exchangers 103a into which the refrigerant flows
according to the operation range of the air conditioning compressor
101 and controlling the corresponding number of solenoid valves 209
for closing, the amount of incoming refrigerant is adjusted so that
the operation range of the air conditioning compressor 101 is not
exceeded.
[0083] However, even if the heat exchanger performance of the
outdoor heat exchanger 103 is reduced by controlling the solenoid
valves 209 to close them, the operation range of the air
conditioning compressor 101 may be deviated in some cases. In such
cases, it is preferable to return the refrigerant to the air
conditioning compressor 101 without allowing it to flow into the
outdoor heat exchanger 103. For this purpose, the solenoid valve
209a installed in the bypass circuit 300 is controlled for opening
and the refrigerant is returned to a suction side of the air
conditioning compressor 101 without allowing the refrigerant to
flow into the outdoor heat exchanger 103. In this way, increase in
evaporation temperature can be prevented and operation can be
carried out while preventing deviation from the operation range of
the air conditioning compressor 101.
[0084] The solenoid valve 209a installed in the bypass circuit 300
is selected so as to satisfy an expression Cva<CVb, where Cva is
a flow rate coefficient of the refrigerant passing through the
outdoor heat exchanger 103 and Cvb is a flow rate coefficient of
the refrigerant passing through the bypass circuit 300. Moreover,
if the operation range of the air conditioning compressor 101
cannot be maintained by division of the heat exchanger capacity,
the operation range is maintained by opening the solenoid valve
209a installed in the bypass circuit 300 to allow the refrigerant
to bypass. The divided structure may be controlled not by the
solenoid valves but by electronic expansion valves.
[0085] FIG. 4 is a flowchart showing a flow of processing in
adjusting the operation range of the air conditioning compressor
101. Based on FIG. 4, the processing in adjusting the operation
range of the air conditioning compressor 101 described in FIG. 3
will be described in detail. As described above, if the air
conditioning and hot water supply complex system 100 is used only
for the normal air conditioning, the heating operation need not be
carried out when the outside-air temperature is relatively high
(e.g., 15.degree. C. or higher) and is generally carried out at the
outside-air wet-bulb temperature of -20.degree. C. to 15.5.degree.
C. If the air conditioning and hot water supply complex system 100
carries out the hot water supply operation, however, it is
necessary to carry out the hot water supply operation irrespective
of the outside-air temperature.
[0086] First, if the air conditioning and hot water supply complex
system 100 starts operation, whether or not a present operation
mode is heating operation is determined (step S101). If the
operation mode is the cooling operation (step S101; NO), the
cooling operation is continued without special control, because the
operation range of the air conditioning compressor 101 is not
exceeded. If the operation mode is the heating operation (step
S101; YES), on the other hand, whether or not the outside-air
temperature is higher than a predetermined temperature A.degree. C.
is determined (step S102). Then, if the outside-air temperature is
A.degree. C. or lower (step S102; NO), the operation range of the
air conditioning compressor 101 is not exceeded and therefore the
heating operation is continued without special control.
[0087] If the outside-air temperature is higher than A.degree. C.
(step S102; YES), on the other hand, whether or not pressure of the
refrigerant drawn into the air conditioning compressor 101 is
pressure not lower than a predetermined acceptable value, i.e.,
saturation pressure for A.degree. C. is determined (step S103). If
the suction pressure is not higher than the saturation pressure for
A.degree. C. (step S103; NO), the operation range of the air
conditioning compressor 101 is not exceeded and therefore the
heating operation is continued without special control. If the
suction pressure is pressure not lower than the saturation pressure
for 21.degree. C. (step S103; YES), on the other hand, it is highly
likely that the operation range of the air conditioning compressor
101 is exceeded and therefore control is carried out to reduce a
rotation number of the air blowing means such as the fan provided
in the vicinity of the outdoor heat exchanger 103 and to determine
the number of solenoid valves 209 to be closed (step S104).
[0088] In other words, by reducing the heat exchanger performance
of the outdoor heat exchanger 103, the suction pressure to the air
conditioning compressor 101 is prevented from exceeding the
acceptable value and the operation range of the air conditioning
compressor 101 is adjusted. Then, whether or not the suction
pressure to the air conditioning compressor 101 is the pressure not
lower than the saturation pressure for the predetermined
temperature 21.degree. C. is determined again (step S105). When the
suction pressure becomes pressure not higher than the saturation
pressure (step S105; NO), it is determined that the operation range
of the air conditioning compressor 101 is not exceeded and
therefore the heating operation is continued with the air blowing
means and the solenoid valves 209 under control. On the other hand,
if the suction pressure is still pressure not lower than the
saturation pressure (step S105; YES), there is still a possibility
that the operation range of the air conditioning compressor 101 is
exceeded and therefore control is carried out to further reduce the
rotation number of the air blowing means and increase the number of
solenoid valves 209 to be closed (step S104).
[0089] In a normal operating state, the predetermined temperature
A.degree. C. is generally determined according to the air
conditioning compressor 101 to be used. The normal air conditioning
compressor 101 has limit values for the suction pressure and
discharge pressure. During the heating operation, the outdoor heat
exchanger 103 normally functions as the evaporator. When the
outdoor heat exchanger 103 is functioning as the evaporator, the
suction pressure of the air conditioning compressor 101 is
substantially similar to the saturation pressure calculated from
the outside-air wet-bulb temperature. Although the operation range
of the air conditioning compressor 101 is determined based on the
outside-air temperature, it may be determined based on a case in
which the air blowing means near the outdoor heat exchanger 103 is
rotating at the lowest speed for a few minutes or a case in which
the air conditioning compressor 101 is rotating at the lowest speed
for a few minutes. The time "a few minutes" mentioned here is equal
to an outdoor unit control timing or a moment.
[0090] The determination and control of the respective devices
based on the flowchart are performed by a controller (not shown)
made up of a microcomputer or the like. This controller may be
provided to any of the heat source unit A, the repeater E, the
cooling indoor unit B, the heating indoor unit C, and the hot water
supply heat source circuit D. Moreover, a low pressure detecting
means such as a pressure sensor for detecting the pressure of the
refrigerant drawn into the air conditioning compressor 101 is
preferably provided in the suction side pipe connected to the air
conditioning compressor 101. The number of divided heat exchangers
103a forming the outdoor heat exchanger 103, i.e., the division
number of the outdoor heat exchanger 103 is not especially
limited.
Second Embodiment
[0091] FIGS. 5(a) and 5(b) are explanatory diagrams for explaining
a hot water supply refrigerating cycle 2a according to an second
embodiment of the invention. Based on FIG. 5, the hot water supply
refrigerating cycle 2a characterizing the second embodiment will be
described. FIG. 5(a) is an enlarged view of a portion of the hot
water supply refrigerating cycle 2a and FIG. 5(b) is an enlarged
view of a portion of the hot water supply refrigerating cycle 2 as
a comparative example. The hot water supply refrigerating cycle 2a
is different from the hot water supply refrigerating cycle 2 in
that the refrigerant pipe 45 is divided between the hot water
supply compressor 21 and the heat medium-refrigerant heat exchanger
51 and that a bypass pipe 45a connected between the hot water
supply throttle means 22 and the refrigerant-refrigerant heat
exchanger 41 is provided to form a bypass circuit 310. A bypass
solenoid valve 309 is installed in the bypass pipe 45a.
[0092] As described above, the heat medium-refrigerant heat
exchanger 51 carries out heat exchange between the refrigerant
circulating through the hot water supply refrigerating cycle 2 and
the heat medium such as water circulating through the hot water
supply load 3. When the heating operation is carried out in the air
conditioning and hot water supply complex system 100, the operation
mode may change to defrosting operation depending on the
outside-air temperature in some cases. If the operation mode
changes to the defrosting operation, a low-pressure refrigerant at
0.degree. C. or a lower temperature may flow into the heat
medium-refrigerant heat exchanger 51a. If the operation mode
changes to the defrosting operation and the low-pressure
refrigerant at 0.degree. C. or a lower temperature flows into the
heat medium-refrigerant heat exchanger 51 according to the first
embodiment, it may circulate through the hot water supply load 3 to
freeze water retained in the heat medium-refrigerant heat exchanger
51.
[0093] Therefore, by adding the bypass pipe 45a to the hot water
supply refrigerating cycle 2a and controlling the bypass solenoid
valve 309 installed in the bypass pipe 45a from a closed state into
an open state, it is possible to prevent the low-pressure
refrigerant from flowing into the heat medium-refrigerant heat
exchanger 51, even if the operation mode changes to the defrosting
operation. As a result, by allowing the low-pressure refrigerant to
flow into the bypass circuit 310 during the defrosting operation,
an acute change in temperature is not caused in the hot water
supply load 3 and it is possible to supply the stable heat source.
Moreover, by allowing the low-pressure refrigerant to bypass
through the bypass pipe 45a, it is possible to prevent the water
retained in the heat medium-refrigerant heat exchanger 51 from
freezing to thereby avoid breakage of the heat medium-refrigerant
heat exchanger 51. Not the bypass solenoid valve 309 but an
electronic expansion valve or a mechanical expansion valve may be
used to allow the low-pressure refrigerant to bypass.
[0094] FIG. 6 is a flowchart showing a flow of processing in
opening and closing the bypass solenoid valve 309. Based on FIG. 6,
processing for controlling opening and closing of the bypass
solenoid valve 309 to allow the refrigerant to pass through the
bypass pipe 45a will be described in detail. As described above,
when the heating operation is carried out in the air conditioning
and hot water supply complex system 100, the operation mode may
change to the defrosting operation in some cases depending on the
outside-air temperature. In such cases, the air conditioning and
hot water supply complex system 100 can carry out the defrosting
operation by controlling the four-way valve 102 to achieve the
similar flow of refrigerant to that in the cooling operation.
[0095] First, if the air conditioning and hot water supply complex
system 100 starts operation, whether or not the present operation
mode is the heating mode is determined (step S201). If the
operation mode is the cooling operation (step S201; NO), the
defrosting operation is not carried out and the refrigerant need
not pass thorough the bypass pipe 45a. Therefore, the bypass
solenoid valve 309 is closed and the cooling operation is
continued. If the operation mode is the heating operation (step
S201; YES), on the other hand, whether or not the outside-air
temperature is a temperature not higher than the predetermined
temperature A.degree. C. is determined (step S202). If the
outside-air temperature is higher than A.degree. C. (step S202;
NO), the defrosting operation is not carried out and the
refrigerant need not pass thorough the bypass pipe 45a. Therefore,
the bypass solenoid valve 309 is closed and the heating operation
is continued.
[0096] If the outside-air temperature is not higher than A.degree.
C. (step S202; YES), on the other hand, necessity for the
defrosting operation is determined based on whether or not a
surface temperature of the outdoor heat exchanger 103 is not higher
than a predetermined temperature (step S203). If the defrosting
operation is unnecessary, i.e., if the surface temperature of the
outdoor heat exchanger 103 is higher than the predetermined
temperature (step S203; NO), it is unnecessary to allow the
refrigerant to pass through the bypass pipe 45a and therefore the
bypass solenoid valve 309 is closed and the heating operation is
continued. On the other hand, if the defrosting operation is
necessary, i.e., the surface temperature of the outdoor heat
exchanger 103 is not higher than the predetermined temperature
(step S203; YES), the defrosting operation is carried out and the
bypass solenoid valve 309 is controlled for opening to allow the
refrigerant to flow through the bypass pipe 45a (step S204).
[0097] Determination based on the flowchart and control of the
respective devices are carried out by the controller similarly to
FIG. 4. It is preferable that a temperature detecting means such as
a temperature sensor for detecting the surface temperature of the
outdoor heat exchanger 103 is provided on or near a surface of the
outdoor heat exchanger 103. The bypass solenoid valve 309 is opened
not only when the defrosting operation starts. For example, if a
flowing direction of the refrigerant is reversed, e.g., when the
mode is switched from the heating operation to the cooling
operation, the low-temperature refrigerant flows into the heat
medium-refrigerant heat exchanger 51 and therefore the bypass
solenoid valve 309 may be opened to allow the refrigerant to flow
into the bypass pipe 45a. In this case, however, it is preferable
that the operation is started after adjusting a flow rate of the
refrigerant so as to avoid an abrupt change in the refrigerant in
the bypass pipe 45a circuit.
Third Embodiment
[0098] FIGS. 7(a) and 7(b) are explanatory diagrams for explaining
a stored hot water circulating pipe 203a according to a third
embodiment of the invention. FIG. 8 is a schematic diagram for
explaining height of a trap 210. Based on FIGS. 7(a) to 8, the
stored hot water circulating pipe 203a characterizing the third
embodiment will be described. FIG. 7(a) is an enlarged view of a
portion of the stored hot water circulating pipe 203a and FIG. 7(b)
is an enlarged view of a portion of a stored hot water circulating
pipe 203 as a comparative example. The stored hot water circulating
pipe 203a is different from the stored hot water circulating pipe
203 in that it forms the trap 210.
[0099] To install the stored hot water circulating pipe 203
according to the first and second embodiments, it is common
practice to directly connect pipes to water side inlet and outlet
of the heat medium-refrigerant heat exchanger 51 as shown in. FIG.
7(b). As a result, when fluid flows in a direction of an arrow, an
air layer builds up in an upper portion of the heat
medium-refrigerant heat exchanger 51. If the air layer builds up in
the upper portion of the heat medium-refrigerant heat exchanger 51,
scale adheres to that portion and it is highly possible that life
of the heat medium-refrigerant heat exchanger 51 is shortened.
[0100] Therefore, the trap 210 is formed in the stored hot water
circulating pipe 203a forming the hot water supply load 3 to
prevent the air layer from building up in the upper portion of the
heat medium-refrigerant heat exchanger 51. The trap 210 is formed
by placing part of the stored hot water circulating pipe 203a on
the exit side of the heat medium-refrigerant heat exchanger 51 in a
higher position than the stored hot water circulating pipe 203a on
the entrance side of the heat medium-refrigerant heat exchanger 51
by A mm. If the trap 210 is formed in the stored hot water
circulating pipe 203a in this way, it is possible to allow the air
layer to build up in the trap 210 and the air layer does not build
up in the upper portion of the heat medium-refrigerant heat
exchanger 51.
[0101] As a result, when the system is used in a high-hardness
water environment, it is possible to prevent the air from building
up in the heat medium-refrigerant heat exchanger 51 in advance to
thereby prevent adhesion of scale and extend the life of the heat
medium-refrigerant heat exchanger 51. The air building up in the
trap 210 can be discharged outside by maximizing the flow rate of
the water circulating pump 31. If the air is discharged at one time
when the pipe is installed, the air does not build up in the trap
210 and the scale does not adhere to an inside of the stored hot
water circulating pipe 203a.
[0102] An air bleeding valve or the like may be provided in the
portion where the trap 210 is formed to remove the air building up
in the trap 210. As shown in FIG. 8, if the height of the trap 210
is A (mm) and height of the heat medium-refrigerant heat exchanger
is B (mm), the height A of the trap 210 is not lower than 0 mm and
not higher than the height B of the heat medium-refrigerant heat
exchanger 51. However, if the water circulating pump 31 is selected
in consideration of the height A of the trap 210, the height A of
the trap 210 is not especially limited.
* * * * *