Refrigerant Circuit (Piping Diagrams)
SiUS371901EB
71
Part 2 Refrigerant Circuit
1. Refrigerant Circuit (Piping Diagrams)
1.1 Outdoor
Unit
No. in
piping
diagram
Electric
symbol
Name
Function
(1)
M1C
Compressor
Compressor is operated on frequencies between 15 rps to 140 rps by
using the inverter. Refer to page 141.
(2)
M1F
M2F
Inverter fan
The fan rotation speed is varied in 53 steps by using inverter. Refer to page
140.
(3)
Y1E
Electronic expansion valve
(Heat exchanger upper)
While in heating, PI control is applied to keep the outlet superheating
degree of air heat exchanger constant.
(4)
Y2E
Electronic expansion valve
(Subcooling heat exchanger)
PI control is applied to keep the outlet superheating degree of subcooling
heat exchanger constant.
(5)
Y3E
Electronic expansion valve
(Heat exchanger lower)
While in heating, PI control is applied to keep the outlet superheating
degree of air heat exchanger constant.
(6)
Y4E
Electronic expansion valve
(Subcooling injection)
Used to control compressor injection.
(7)
Y5E
Electronic expansion valve
(Refrigerant cooling)
Used to control the refrigerant amount to cool the diode bridge and power
module of the inverter PCB.
(8)
Y7E
Electronic expansion valve
(Receiver gas purge)
Used to collect the refrigerant to receiver.
(9)
Y1S
Solenoid valve
(Oil separator oil return)
Used to return oil from the oil separator to the compressor.
(10)
Y2S
Solenoid valve (Hot gas bypass) Used to flow discharge gas to the compressor inlet.
(11)
Y3S
Solenoid valve (Liquid shutoff)
Used to shut off liquid refrigerant flow to the receiver.
(12)
Y4S
Four way valve
(HP/LP gas pipe)
Used to switch dual pressure gas pipe to high pressure or low pressure.
(13)
Y5S
Four way valve
(Heat exchanger lower)
Used to switch outdoor heat exchanger to evaporator or condenser.
(14)
Y6S
Four way valve
(Heat exchanger upper)
(15)
Y7S
Solenoid valve
(Accumulator oil return)
Used to return oil from the accumulator to the compressor.
(16)
S1NPH High pressure sensor
Used to detect the high pressure.
(17)
S1NPL Low pressure sensor
Used to detect the low pressure.
(18)
S1PH
High pressure switch
This functions when pressure increases to stop operation and avoid high
pressure increase in the fault operation.
(19)
—
Pressure regulating valve
(Liquid pipe)
This is used when pressure increases, to prevent any damage on
components caused by pressure increase in transport or storage.
(20)
—
Subcooling heat exchanger
Apply subcooling to liquid refrigerant.
(21)
—
Capillary tube
Used to return the refrigerating oil separated through the oil separator to
the compressor.
(22)
R1T
Thermistor (Outdoor air)
Used to detect outdoor air temperature, correct discharge pipe
temperature and for other purposes.
(23)
R21T
Thermistor (M1C discharge)
Used to detect discharge pipe temperature.
(24)
R3T
Thermistor (Receiver inlet)
Used to detect liquid pipe temperature of receiver inlet.
(25)
R4T
Thermistor
(Heat exchanger liquid upper)
This detects temperature of liquid pipe for air heat exchanger.
(26)
R5T
Thermistor
(Heat exchanger liquid lower)
(27)
R6T
Thermistor (Subcooling gas)
This detects temperature of gas pipe for subcooling heat exchanger.
(28)
R7T
Thermistor (Subcooling liquid)
This detects temperature of liquid pipe for subcooling heat exchanger.
(29)
R8T
Thermistor
(Heat exchanger gas upper)
This detects temperature of gas pipe for air heat exchanger.
(30)
R9T
Thermistor
(Heat exchanger gas lower)
(31)
R10T
Thermistor (Suction pipe)
Used to detect suction pipe temperature.
(32)
R11T
Thermistor (Deicer)
Used to detect liquid pipe temperature of air heat exchanger. Used to make
judgements on defrost operation.
Summary of Contents for REYQ72-432XAYCU
Page 455: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 448 REYQ144 168XATJU REYQ144 168XATJA 2D119206B ...
Page 457: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 450 REYQ144 168XAYDU REYQ144 168XAYDA 2D119208C ...
Page 461: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 454 FXZQ05 07 09 12 15 18TAVJU 3D110443A ...
Page 463: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 456 FXEQ07 09 12 15 18 24PVJU 3D098557A ...
Page 464: ...Wiring Diagrams SiUS371901EB 457 Part 7 Appendix FXDQ07 09 12 18 24MVJU C 3D050501C ...
Page 468: ...Wiring Diagrams SiUS371901EB 461 Part 7 Appendix FXHQ12 24 36MVJU 3D048116C ...
Page 469: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 462 FXAQ07 09 12 18 24PVJU 3D075354F ...
Page 475: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 468 VAM1200GVJU 3D073270D ...
Page 478: ...Wiring Diagrams SiUS371901EB 471 Part 7 Appendix BS6 8Q54TVJ 2D089122B ...
Page 479: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 472 BS10 12Q54TVJ 2D089121B ...
Page 481: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 474 BSF6 8Q54TVJ 2D123905A ...