FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
REFRIGERATION CYCLE DEVICE;
MITSUBISHI ELECTRIC CORPORATION, A CORPORATION ORGANISED AND
EXISTING UNDER THE LAWS OF JAPAN, WHOSE ADDRESS IS 7-3,
MARUNOUCHI 2-CHOME, CHIYODA-KU, TOKYO 100-8310, JAPAN
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE
INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.
5
2
DESCRIPTION
TECHNICAL FIELD
[0001] The present disclosure relates to a refrigeration cycle device.
BACKGROUND ART
5 [0002] A refrigeration cycle device is known which uses a mixed refrigerant that
contains trifluoroiodomethane (CF3I) having low global warming potentials, as a
refrigerant that circulates around a refrigerant circuit. A refrigeration cycle device is
known which manages the temperature of a refrigerant discharged from a compressor
in the refrigeration cycle (hereinafter, a discharge temperature) so as to not exceed a
10 predetermined temperature because CF3I, when raised to a high temperature, has
negative impact on thermochemical stabilities. For example, a refrigeration cycle
device disclosed in PTL 1 includes: a refrigeration cycle which circulates a refrigerant
containing CF3I, the refrigeration cycle including a compressor, a condenser, an
evaporator, and an evaporator-side expansion valve; an suction pressure sensor for
15 measuring the suction pressure of the refrigerant suctioned into the compressor; a
discharge pressure sensor for measuring the discharge pressure of the refrigerant
discharged from the compressor; and a control means which opens the injection valve
to the compressor and reduces the discharge temperature if the discharge temperature
estimated from the suction pressure and the discharge pressure is greater than or equal
20 to a predetermined value.
CITATION LIST
PATENT LITERATURE
[0003] PTL 1: WO2020/039707
SUMMARY OF INVENTION
25 TECHNICAL PROBLEM
[0004] HFO1123 having low global warming potentials and a great gas density may be
desired to be added to a mixed refrigerant. However, the use of such a mixed
refrigerant that contains CF3I and HFO1123 causes the following problem.
[0005] Since HFO1123 has characteristics of causing a disproportionation reaction, it is
3
contemplated that a refrigerant that contains a large amount of CF3I, which has a
suppressive effects on the disproportionation reaction, is injected to the compressor.
However, a low ratio of CF3I in the refrigerant cannot suppress the disproportionation
reaction. In contrast, a high ratio of CF3I in in the refrigerant, for purpose of
5 suppressing the disproportionation reaction, deteriorates the performance of the
refrigeration cycle device.
[0006] Therefore, an object of the present disclosure is to provide a refrigeration cycle
device that can suppress the disproportionation reaction and prevent deterioration of the
performance of the refrigeration cycle device.
10 SOLUTION TO PROBLEM
[0007] A refrigeration cycle device according to the present disclosure includes: a
refrigerant circuit which circulates a mixed refrigerant containing at least CF3I and
HFO1123, the refrigerant circuit including a compressor, an expansion valve, an indoor
heat exchanger, an outdoor heat exchanger, and a refrigerant reservoir; an injection pipe
15 which includes a first end at a first height within the refrigerant reservoir and a second
end connected to the compressor; and an injection valve included in the injection pipe.
the CF3I has a greatest fluid density among refrigerants contained in the mixed
refrigerant. The first height is lower than a height at which an end of a refrigerant
pipe, other than the injection pipe, is located within the refrigerant reservoir.
20 ADVANTAGEOUS EFFECTS OF INVENTION
[0008] According to the present disclosure, the disproportionation reaction can be
suppress and the deterioration of performance of the refrigeration cycle device can be
suppressed.
BRIEF DESCRIPTION OF DRAWINGS
25 [0009] Fig. 1 is a diagram depicting a configuration of a refrigeration cycle device
1000 according to Embodiment 1.
Fig. 2 is a flowchart illustrating a procedure for controlling an injection valve
400.
Fig. 3 is a diagram depicting a configuration of a refrigeration cycle device
4
1001 according to Embodiment 2.
Fig. 4 is a diagram depicting a configuration of a refrigeration cycle device
1002 according to Embodiment 3.
Fig. 5 is a diagram depicting a configuration of a refrigeration cycle device
5 1003 according to Embodiment 4.
Fig. 6 is a diagram depicting a configuration of a refrigeration cycle device
1004 according to Embodiment 5.
DESCRIPTION OF EMBODIMENTS
[0010] Hereinafter, embodiments will be described, with reference to the
10 accompanying drawings.
Embodiment 1
Fig. 1 is a diagram depicting a configuration of a refrigeration cycle device
1000 according to Embodiment 1.
[0011] The refrigeration cycle device 1000 includes an indoor unit 100 and an outdoor
15 unit 200. While Fig. 1 shows one indoor unit 100, the refrigeration cycle device 1000
may include multiple indoor units 100.
[0012] The outdoor unit 200 includes an outdoor heat exchanger 210, an outdoor fan
220, a compressor 230, a flow switch (a flow switch valve) 240, a first expansion valve
250, a second expansion valve 260, a receiver (a refrigerant container) 500, an injection
20 valve 400, and a discharge temperature sensor 11. The receiver 500 is one example of
the refrigerant reservoir.
[0013] The indoor unit 100 includes an indoor heat exchanger 110 and an indoor fan
120.
The outdoor fan 220 is disposed near the outdoor heat exchanger 210. The
25 indoor fan 120 is disposed near the indoor heat exchanger 110.
[0014] The compressor 230, the flow switch 240, the first expansion valve 250, the
second expansion valve 260, the receiver (the refrigerant container) 500, and the indoor
heat exchanger 110 form a refrigerant circuit RC. A mixed refrigerant circulates
around the refrigerant circuit RC. The mixed refrigerant contains at least CF3I and
5
HFO1123. CF3I has the largest fluid density among refrigerants contained in the
mixed refrigerant.
[0015] Three conditions, which are a high pressure, a high temperature, and external
energy, are satisfied, a disproportionation reaction takes place. Thus, a
5 disproportionation reaction is likely to occur at the compressor 230 in the refrigerant
circuit RC. If at least a large amount CF3I, among the total amount, flows into the
compressor 230, the disproportionation reaction can be suppressed and the deterioration
of the performance of the refrigeration cycle device 1000 can be prevented. CF3I has
a fluid density about 2.2 times the fluid density of HFO1123. Accordingly, as the
10 mixed refrigerant flows into the receiver 500, CF3I is likely to be accumulated deep
within the receiver 500. In the present embodiment, the amount of CF3I in the
compressor 230 is increased by injecting into the compressor 230 the refrigerant deep
within the receiver 500.
[0016] The refrigerant circuit RC includes refrigerant pipes 51, 52, 53, 54, 251, and
15 261.
The flow switch 240 is formed of a four-way valve, for example.
[0017] The flow switch 240 has a first opening P1 connected to the compressor 230 by
the refrigerant pipe (a first refrigerant pipe) 54.
[0018] The flow switch 240 has a second opening P2 connected to the outdoor heat
20 exchanger 210 by the refrigerant pipe (a second refrigerant pipe) 52.
[0019] The flow switch 240 has a third opening P3 connected to the compressor 230 by
the refrigerant pipe 51 (a third refrigerant pipe). A portion of the refrigerant pipe 51
passes inside the receiver 500. This causes the mixed refrigerant flowing through the
refrigerant pipe 51 and the mixed refrigerant in the receiver 500 to exchange heat.
25 The lowest portion of the refrigerant pipe 51 in the vertical direction will be referred to
as HP.
[0020] The flow switch 240 has a fourth opening P4 connected to the indoor heat
exchanger 110 by the refrigerant pipe 53 (a fourth refrigerant pipe).
[0021] The refrigerant pipe (a fifth refrigerant pipe) 251 has a first end at a second
6
height H2 within the receiver 500 in the vertical direction, and a second end connected
to the outdoor heat exchanger 210. The refrigerant pipe 251 includes the first
expansion valve 250.
[0022] The refrigerant pipe (a sixth refrigerant pipe) 261 has a first end at a third height
5 H3 within the receiver 500 in the vertical direction, and a second end connected to the
indoor heat exchanger 110. The refrigerant pipe 261 includes the second expansion
valve 260.
[0023] The outdoor unit 200 includes an injection pipe 401 and the injection valve 400.
[0024] The injection pipe 401 has a first end at a first height H1 within the receiver 500
10 in the vertical direction, and a second end connected to the compressor 230. The
injection valve 400 is included in the injection pipe 401. The injection valve 400 may
be a solenoid operated valve that can turn on/off, or an electronic expansion valve that
can change the valve travel.
[0025] As shown in Fig. 1, a mixed refrigerant is accumulated in the receiver 500.
15 Fig. 1 shows a liquid level L. A gas refrigerant is accumulated above the liquid level
L, and a liquid refrigerant is accumulated below the liquid level L.
[0026] The first height H1 is lower than a height at which an end of a refrigerant pipe,
other than the injection pipe 401, is located within the receiver 500. Specifically, H2
is higher than H1 and H3 is higher than H1. H2 may be equal to H3 or H2 may not be
20 equal to H3. HP may be greater than H2 and HP may be greater than H3.
[0027] While the refrigeration cycle device 1000 is in operation, the refrigerants
contained in the mixed refrigerant are not perfectly separated by fluid density in the
receiver 500. However, the deeper within the receiver 400, the greater the ratio of
CF3I is. Since H2 is greater than H1 and H3 is greater than H1, CF3I, which has the
25 largest fluid density, can be the primary component of the refrigerant injected from the
receiver 500 to the compressor 230 through the injection pipe 401 and the injection
valve 400. This yields advantageous effects of suppressing the disproportionation
reaction if, for example, the mass ratio of CF3I is greater by 2wt% than the mass ratio
of HFO1123 being 60% in the compressor 230, and advantageous effects of sufficiently
7
suppressing the occurrence of the disproportionation reaction if the mass ratio of CF3I
is about 5%.
[0028] In the compressor 230, the total amount of R32, HFO1123, and CF3I to the
mixed refrigerant is, preferably, 99.5 wt% or greater, more preferably, 99.7wt% or
5 greater, and, most preferably, 99.9wt% or greater.
[0029] While the refrigeration cycle device 1000 is not in operation, the refrigerants
contained in the mixed refrigerant is almost fully classified by fluid density in the
receiver 500. CF3I is accumulated deepest within the receiver 500. H2 may be
greater than S, H3 may be greater than S, and S may be greater than H1, where S
10 denotes the height of the surface of separation of CF3I from the other refrigerants such
as HFO1123.
[0030] The control device 10 opens the injection valve 400, thereby injecting the
refrigerant having a low temperature from the receiver 500 to the compressor 230 and
cooling the compressor 230. This reduces the discharge temperature of the
15 compressor 230.
[0031] The control device 10 controls the drive frequency of the compressor 230,
thereby controlling the amount of mixed refrigerant discharged by the compressor 230
per unit time so that the temperature inside the indoor unit 100, obtained by a
temperature sensor not shown, is a desired temperature (e.g., a temperature set by a
20 user).
[0032] The control device 10 controls the valve travels of the first expansion valve 250
and the second expansion valve 260 so that the degree of superheat or supercooling of
the mixed refrigerant has a value within a desired range. While the refrigeration cycle
device 1000 is in the cooling operation, the first expansion valve 250 controls the
25 degree of supercooling of the mixed refrigerant at the outlet of the outdoor heat
exchanger 210 or the intermediate pressure of the receiver 500, and the second
expansion valve 260 controls the degree of suction superheat of the mixed refrigerant
suctioned into the compressor 230 (hereinafter, a degree of suction superheat), the
temperature of the mixed refrigerant discharged from the compressor 230 (hereinafter,
8
a discharge temperature), and the degree of discharge superheat of the mixed
refrigerant discharged from the compressor 230 (hereinafter, a degree of discharge
superheat). While the refrigeration cycle device 1000 is in the heating operation, the
first expansion valve 250 controls the degree of suction superheat, the discharge
5 temperature, and the degree of discharge superheat, and the second expansion valve
260 controls the degree of supercooling of the refrigerant at the outlet of the indoor heat
exchanger 110 or the intermediate pressure of the indoor heat exchanger 110.
[0033] The control device 10 controls air delivery rates per unit time from the outdoor
fan 220 and the indoor fan 120.
10 [0034] The control device 10 obtains a discharge temperature Td from the discharge
temperature sensor 11, which is the temperature of the mixed refrigerant discharged
from the compressor 230. The control device 10 controls the valve travel of the
injection valve 400, based on the discharge temperature Td.
[0035] The control device 10 controls the flow switch 240, thereby changing the
15 direction of circulation of the mixed refrigerant.
During the cooling operation, the control device 10 connects the first opening
P1 and the second opening P2 of the flow switch 240, and the third opening P3 and the
fourth opening P4. This brings the discharge port of the compressor 230 and the
outdoor heat exchanger 210 into communication, and the indoor heat exchanger 110
20 and the inlet of the compressor 230 into communication.
[0036] During the cooling operation, the mixed refrigerant circulates in order from the
compressor 230, the flow switch 240, the outdoor heat exchanger 210, the first
expansion valve 250, the receiver 500, the second expansion valve 260, the indoor heat
exchanger 110, the flow switch 240, the receiver 500, and the compressor 230. CF3I,
25 contained in the mixed refrigerant flown from the first expansion valve 250 into the
receiver 500, which has a great fluid density, can mostly be injected to the compressor
230 through the injection pipe 401 and the injection valve 400.
[0037] During the heating operation, the control device 10 connects the first opening
P1 and the fourth opening P4 of the flow switch 240, and the second opening P2 and
9
the third opening P3. This brings the discharge port of the compressor 230 and the
indoor heat exchanger 110 into communication, and the outdoor heat exchanger 210
and the inlet of the compressor 230 into communication.
[0038] During the heating operation, the mixed refrigerant circulates in order from the
5 compressor 230, the flow switch 240, the indoor heat exchanger 110, the second
expansion valve 260, the receiver 500, the first expansion valve 250, the outdoor heat
exchanger 210, the flow switch 240, the receiver 500, and the compressor 230. CF3I,
contained in the mixed refrigerant flown from the second expansion valve 260 into the
receiver 500, which has a great fluid density, can mostly be injected to the compressor
10 230 through the injection pipe 401 and the injection valve 400.
[0039] Fig. 2 is a flowchart illustrating a procedure for controlling the injection valve
400.
In step S11, the control device 10 obtains the frequency of the compressor 230.
[0040] In step S12, the control device 10 determines an optimal valve travel for the
15 injection valve 400 in accordance with the frequency of the compressor 230, and
changes the valve travel of the injection valve 400 to the determined valve travel.
[0041] If the injection valve 400 has a small valve travel, a large amount of CF3I flows
into the evaporator (the indoor heat exchanger 110 or the outdoor heat exchanger 210),
and the performance of the refrigeration cycle device 1000 is thereby deteriorated. If
20 the injection valve 400 has a large valve travel, too much CF3I is injected into the
compressor 230. As a result, the performance of the refrigeration cycle device 1000
deteriorates. The performance of the refrigeration cycle device 1000 can be enhanced
by the control device 10 changing the valve travel of the injection valve 400 to an
optimal valve travel.
25 [0042] In step S13, the control device 10 obtains the discharge temperature Td of the
compressor 230 from the discharge temperature sensor 11. If the discharge
temperature Td is greater than a reference value TH, the control device 10 proceeds to
step S14. If the discharge temperature Td is not greater than the reference value TH,
the process ends. The reference value TH is determined by experiment or simulation.
10
[0043] In step S14, the control device 10 increases the valve travel of the injection
valve 400. This can reduce the discharge temperature.
[0044] As described above, according to the present embodiment, the amount of CF3I
in the compressor 230 can be increased by injecting the refrigerant deeper within the
5 receiver 500 to the compressor 230 through the injection pipe 401 and the injection
valve 400. This obviates the need to increase the amount of CF3I contained in the
mixed refrigerant for purpose of suppressing the occurrence of the disproportionation
reaction. Thus, according to the present embodiment, the disproportionation reaction
can be suppressed and the deterioration of the performance of the refrigeration cycle
10 device 1000 can be prevented.
[0045] Embodiment 2
Fig. 3 is a diagram depicting a configuration of a refrigeration cycle device
1001 according to Embodiment 2.
[0046] The refrigeration cycle device 1001 includes an outdoor unit 201, and an indoor
15 unit 100 which is the same as one according to Embodiment 1.
[0047] The outdoor unit 201 according to Embodiment 2 differs from the outdoor unit
200 according to Embodiment 1 in that the outdoor unit 201 according to Embodiment
2 includes a refrigerant pipe 51A, instead of the refrigerant pipe 51.
[0048] The refrigerant pipe 51A does not pass inside the receiver 500. Accordingly, a
20 mixed refrigerant flowing through the refrigerant pipe 51A exchange no heat with a
mixed refrigerant in the receiver 500.
[0049] According to the present embodiment, the refrigerant pipe 51A has a reduced
length shorter than the refrigerant pipe 51 according to Embodiment 1, thereby
achieving a reduced cost of the refrigeration cycle device.
25 [0050] Embodiment 3
Fig. 4 is a diagram depicting a configuration of a refrigeration cycle device
1002 according to Embodiment 3.
[0051] The refrigeration cycle device 1002 includes an outdoor unit 202, and an indoor
unit 100 which is the same as one according to Embodiment 1.
11
[0052] The outdoor unit 202 according to Embodiment 3 differs from the outdoor unit
201 according to Embodiment 2 in that the outdoor unit 202 according to Embodiment
3 does not include the first expansion valve 250.
[0053] In the present embodiment, the second expansion valve 260 controls the degree
5 of suction superheat, the discharge temperature, and the degree of discharge superheat
during the cooling operation and the heating operation.
[0054] According to the present embodiment, there is no need to provide the first
expansion valve 250, thereby achieving a reduced cost of the refrigeration cycle device.
[0055] Embodiment 4
10 Fig. 5 is a diagram depicting a configuration of a refrigeration cycle device
1003 according to Embodiment 4.
[0056] The refrigeration cycle device 1003 includes an outdoor unit 203, and an indoor
unit 100 which is the same as one according to Embodiment 1.
[0057] The outdoor unit 203 according to Embodiment 4 differs from the outdoor unit
15 201 according to Embodiment 2 in that the outdoor unit 203 according to Embodiment
4 includes a gas bypass pipe 271 and a bypass valve 270.
[0058] The gas bypass pipe 271 has a first end at a fourth height H4 within the receiver
500 in the vertical direction, and a second end connected to a refrigerant pipe 51A.
H4 is greater than H1, H4 is greater than H2, and H4 is greater than H3.
20 [0059] The bypass valve 270 is included in the gas bypass pipe 271.
The mixed refrigerant in a gaseous state in the receiver 501 is sent to the suction
side of the compressor 230 through the gas bypass pipe 271, the bypass valve 270, and
the refrigerant pipe 51A.
[0060] The bypass valve 270 may have a fixed restriction like a capillary tube, or an
25 electronic expansion valve that can change the valve travel.
[0061] According to the present embodiment, a portion of the mixed refrigerant flows
on a second flow path directly from the receiver to the compressor, bypassing a first
flow path from the receiver to the compressor via the evaporator (the outdoor heat
exchanger or the indoor heat exchanger). This can suppress the pressure drop of the
12
evaporator, and achieve an enhanced performance of the refrigeration cycle device.
[0062] Embodiment 5
Fig. 6 is a diagram depicting a configuration of a refrigeration cycle device
1004 according to Embodiment 5.
5 [0063] The refrigeration cycle device 1004 includes an outdoor unit 204, and an indoor
unit 100 which is the same as one according to Embodiment 1.
[0064] The outdoor unit 204 according to Embodiment 5 differs from the outdoor unit
201 according to Embodiment 2 in that the outdoor unit 204 according to Embodiment
5 does not include the first expansion valve 250, and includes a refrigerant pipe 51B,
10 instead of the refrigerant pipes 51A and 251. The refrigeration cycle device 1004
according to Embodiment 5 includes a refrigerant pipe 59, instead of the refrigerant
pipe 261.
[0065] The refrigerant pipe (a third refrigerant pipe) 51B has a first end at a fifth height
H5 within the receiver 500 in the vertical direction, and a second end connected to the
15 third opening P3 of a flow switch.
[0066] The refrigerant pipe (a seventh refrigerant pipe) 59 has a first end at a sixth
height H6 within the receiver 500 in the vertical direction, and a second end connected
to the suction side of the compressor 230.
[0067] Here, H5 is greater than H1, and H5 is greater than H6 which is greater than H1.
20 A refrigerant pipe (an eighth refrigerant pipe) 290 is disposed outside the
receiver 500. The refrigerant pipe 290 connects an outdoor heat exchanger 210 and an
indoor heat exchanger 110. The refrigerant pipe 290 includes an expansion valve 291.
[0068] The present embodiment has a simplified configuration of the refrigeration
cycle device, and thus can achieve a reduced cost of the refrigeration cycle device.
25 [0069] Variations
(1) While a mixed refrigerant is injected to the compressor in the embodiments
above, the present disclosure is not limited thereto. The present disclosure has similar
advantageous effects by, for example, injecting the mixed refrigerant to the suction side
(a suction pipe) of the compressor.
13
[0070] (2) While the receiver is used as the refrigerant reservoir in the embodiments
above, the present disclosure is not limited thereto. For example, an internal heat
exchanger that exchanges heat between a high-pressure refrigerant and a low-pressure
refrigerant may be used as the refrigerant reservoir.
5 [0071] The presently disclosed embodiment should be considered in all aspects as
illustrative and not restrictive. The scope of the present disclosure is indicated by the
appended claims, rather than by the description above, and all changes that come within
the scope of the claims and the meaning and range of equivalency of the claims are
intended to be embraced within their scope.
10 [0072] REFERENCE SIGNS LIST
10 control device; 11 discharge temperature sensor; 51, 51A, 51B, 52, 53,
54, 59, 251, 261, 290 refrigerant pipe; 100 indoor unit; 110 indoor heat
exchanger; 120 indoor fan; 200, 201, 202, 203, 204 outdoor unit; 210 outdoor
heat exchanger; 220 outdoor fan; 230 compressor; 240 flow switch; 250 first
15 expansion valve; 260 second expansion valve; 270 bypass valve; 271 gas bypass
pipe; 291 expansion valve; 400 injection valve; 401 injection pipe; 500 receiver;
1000, 1001, 1002, 1003, 1004 refrigeration cycle device; P1 first opening; P2
second opening; P3 third opening; P4 fourth opening; and RC refrigerant circuit.
20
14
WE CLAIM:
1. A refrigeration cycle device comprising:
a refrigerant circuit which circulates a mixed refrigerant containing at least
5 CF3I and HFO1123, the refrigerant circuit including a compressor, an expansion valve,
an indoor heat exchanger, an outdoor heat exchanger, and a refrigerant reservoir;
an injection pipe which includes a first end at a first height within the
refrigerant reservoir and a second end connected to the compressor; and
an injection valve included in the injection pipe, wherein
10 the CF3I has a greatest fluid density among refrigerants contained in the mixed
refrigerant, and
the first height is lower than a height at which an end of a refrigerant pipe, other
than the injection pipe, is located within the refrigerant reservoir.
15 2. The refrigeration cycle device according to claim 1, comprising
a control device that increases a valve travel of the injection valve when a
refrigerant discharged from the compressor has a temperature higher than a reference
value.
20 3. The refrigeration cycle device according to claim 1 or 2, wherein
the refrigerant circuit further includes:
a flow switch;
a first refrigerant pipe connecting a discharge side of the compressor and a first
opening of the flow switch,
25 a second refrigerant pipe connecting the outdoor heat exchanger and a second
opening of the flow switch,
a third refrigerant pipe connecting a suction side of the compressor and a third
opening of the flow switch, and
a fourth refrigerant pipe connecting the indoor heat exchanger and a fourth
15
opening of the flow switch.
4. The refrigeration cycle device according to claim 3, wherein
the refrigerant circuit further includes
5 a fifth refrigerant pipe having a first end at a second height within the
refrigerant reservoir and a second end connected to the outdoor heat exchanger,
wherein
the second height is higher than the first height.
10 5. The refrigeration cycle device according to claim 4, wherein
the fifth refrigerant pipe includes the expansion valve.
6. The refrigeration cycle device according to claim 3, wherein
the refrigerant circuit further includes
15 a sixth refrigerant pipe having a first end at a third height within the refrigerant
reservoir and a second end connected to the indoor heat exchanger, wherein
the third height is higher than the first height.
7. The refrigeration cycle device according to claim 6, wherein
20 the sixth refrigerant pipe includes the expansion valve.
8. The refrigeration cycle device according to claim 3, wherein
the refrigerant circuit further includes:
a fifth refrigerant pipe having a first end at a second height within the
25 refrigerant reservoir and a second end connected to the outdoor heat exchanger; and
a sixth refrigerant pipe having a first end at a third height within the refrigerant
reservoir and a second end connected to the indoor heat exchanger, wherein
the fifth refrigerant pipe includes a first of the expansion valve,
the sixth refrigerant pipe includes a second of the expansion valve,
16
the second height is higher than the first height, and
the third height is higher than the first height.
9. The refrigeration cycle device according to claim 8, wherein
5 the third refrigerant pipe passes inside the refrigerant reservoir.
10. The refrigeration cycle device according to claim 8, wherein
the third refrigerant pipe does not pass inside the refrigerant reservoir.
10 11. The refrigeration cycle device according to claim 10, further comprising
a gas bypass pipe having a first end at a fourth height within the refrigerant
reservoir and a second end connected to the third refrigerant pipe; and
a bypass valve included in the gas bypass pipe, wherein
the fourth height is higher than the first height, the second height, and the third
15 height.
12. The refrigeration cycle device according to claim 1 or 2, wherein
the refrigerant circuit further includes:
a flow switch;
20 a first refrigerant pipe connecting a discharge side of the compressor and a first
opening of the flow switch;
a second refrigerant pipe connecting the outdoor heat exchanger and a second
opening of the flow switch;
a third refrigerant pipe having a first end at a fifth height within the refrigerant
25 reservoir and a second end connected to a third opening of the flow switch;
a fourth refrigerant pipe connecting the indoor heat exchanger and a fourth
opening of the flow switch; and
a seventh refrigerant pipe having a first end at a sixth height within the
refrigerant reservoir and a second end connected to a suction side of the compressor,
17
wherein
the fifth height is higher than the first height, and
the sixth height is higher than the first height and lower than the fifth height.
5 13. The refrigeration cycle device according to claim 12, wherein
the refrigerant circuit further includes
an eighth refrigerant pipe disposed outside the refrigerant reservoir and
connecting the outdoor heat exchanger and the indoor heat exchanger, wherein
the eighth refrigerant pipe includes the expansion valve.