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Refrigerant Circuit
SiUS34-801A_b
134
VRVIII R-410A Heat Recovery 60Hz
2.4
REMQ96, 120PYDN, PTJU (Multi 8, 10ton)
No. in refrigerant
system diagram
Symbol
Name
Major Function
1
M1C
Inverter compressor (INV)
Inverter compressor is operated on frequencies between 52Hz and
210Hz by using the inverter, while Standard compressor is operated with
commercial power supply only. The number of operating steps is as
follows when Inverter compressor is operated in combination with
Standard compressor. Compressor operation steps : Refer to page 190.
2
M2C
Standard compressor 1 (STD1)
4
M1F
Inverter fan
Since the system is of
the outdoor unit heat exchanging type, the fan is operated at 9-step
rotation speed by using the inverter.
6
Y1E
Electronic expansion valve (Main: EVM)
While in heating operation, PI control is applied to keep the outlet
superheated degree of
the outdoor unit heat exchanger constant.
7
Y3E
Electronic expansion valve (Subcool: EVT)
PI control is applied to keep the outlet superheated degree of subcooling
heat exchanger constant.
8
Y2E
Electronic expansion valve (Refrigerant charge
EVJ)
Opens/closes refrigerant charge port.
9
Y6S
Solenoid valve (Main bypass SVE)
Opens in cooling operation.
10
Y5S
Solenoid valve (Hot gas: SVP)
Prevents the low pressure from transient fallingreducing.
11
Y4S
Solenoid valve (Refrigerant regulator liquid
pipe SVL)
Collects refrigerant to the refrigerant regulator.
12
Y1S
Solenoid valve (Refrigerant regulator gas purging
pipe SVG)
Collects refrigerant to the refrigerant regulator.
13
Y7S
Solenoid valve (Refrigerant regulator
discharge pipe SVO)
Discharges refrigerant from the refrigerant regulator.
14
Y8S
Solenoid valve (Discharge pipe of refrigerant
regulator)
Bypasses the high pressure gas to the refrigerant regulator.
15
Y3S
4-way valve (Heat exchanger switch 20SA)
Switches outdoor heat exchanger to evaporator or condenser.
16
Y2S
4-way valve (Dual pressure gas pipe switch
20SB)
Switches dual pressure gas pipe to high pressure or low pressure.
17
S1NP
H
High pressure sensor
Detects high pressure.
18
S2NP
L
Low pressure sensor
Detects low pressure.
19
S1PH
HP pressure switch (For INV compressor)
Functions when pressure increases to stop operation and avoid high
pressure increase in the event of a fault.
20
S2PH
HP pressure switch (For STD compressor 1)
22
—
Pressure regulating valve (Liquid pipe)
Used when pressure increases, to prevent any damage on components
caused by pressure increase in transport or storage.
23
—
Pressure regulating valve (Refrigerant
regulator)
Used when pressure increases, to prevent any damage on components
caused by pressure increase in transport or storage.
24
—
Subcooling heat exchanger
Appies subcooling to liquid refrigerant.
25
—
Refrigerant regulator
Surplus refrigerant is held according to the operation conditions.
26
—
Capillary tube
Returns the refrigerating oil separated through the oil separator to the INV
compressor.
27
—
Capillary tube
Returns the refrigerating oil separated through the oil separator to the STD1
compressor.
29
—
Capillary tube
Discharges refrigerant from the refrigerant regulator.
30
R1T
Thermistor (Outdoor air: Ta)
Detects outdoor temperature, correct discharge pipe temperature, and
others.
31
R8T
Thermistor (Suction pipe: TsA)
Detects suction pipe temperature.
32
R31T
Thermistor (INV discharge pipe: Tdi)
Detects discharge pipe temperature. Used for compressor temperature
protection control.
33
R32T
Thermistor (STD1 discharge pipe: Tds1)
35
R4T
Thermistor (Heat exchanger deicer: Tb)
Detects liquid pipe temperature of
the outdoor unit heat exchanger. Used to
make judgments on defrosting operation.
36
R2T
Thermistor (Heat exchanger gas pipe Tg)
Detects temperature of gas pipe for
the outdoor unit heat exchanger. Used to
exercise the constant control of superheated degree when an evaporator is
used for outdoor unit heat exchanging.
37
R7T
Thermistor (Heat exchanger liquid pipe Tf)
Detects temperature of liquid pipe between the
the outdoor unit heat
exchanger and main electronic expansion valve. Used to make judgments
on the recover or discharge refrigerants to the refrigerant regulator.
38
R5T
Thermistor (Subcooling heat exchanger gas
pipe: Tsh)
Detects gas pipe temperature on the evaporation side of subcooling heat
exchanger. Used to exercise the constant control of superheated degree
at the outlet of subcooled heat exchanger.
39
R6T
Thermistor (Subcooling heat exchanger liquid
pipe Tl)
Detects temperature of liquid pipe between the main expansion valve and
subcooling heat exchanger.
40
R9T
Thermistor (Liquid pipe Tsc)
Detects temperature of liquid pipe between the liquid stop valve and subcooling heat
exchanger.
Summary of Contents for VRV III
Page 15: ...SiUS34 801A_b xiv ...
Page 23: ...Model Selection SiUS34 801A_b 8 General Information ...
Page 133: ...Field Settings SiUS34 801A_b 118 VRVIII R 410A Heat Pump 60Hz ...
Page 254: ...SiUS34 801A_b Test Operation VRVIII R 410A Heat Recovery 60Hz 239 R 410A Label R 410A Label ...
Page 329: ...Field Setting SiUS34 801A_b 314 Indoor Unit ...
Page 340: ...SiUS34 801A_b Troubleshooting by Remote Controller Troubleshooting 325 ...
Page 490: ...SiUS34 801A_b Piping Diagrams Appendix 475 Heat Pump 230V RXYQ72 96 120PTJU 3D058636A ...
Page 491: ...Piping Diagrams SiUS34 801A_b 476 Appendix Heat Pump 230V RXYQ144PTJU 3D058640 ...
Page 492: ...SiUS34 801A_b Piping Diagrams Appendix 477 Heat Recovery 460V REYQ72 96 120PYDN 3D058639A ...
Page 493: ...Piping Diagrams SiUS34 801A_b 478 Appendix Heat Recovery 460V REMQ72PYDN 3D058637A ...
Page 494: ...SiUS34 801A_b Piping Diagrams Appendix 479 Heat Recovery 460V REMQ96 120PYDN 3D058638A ...
Page 495: ...Piping Diagrams SiUS34 801A_b 480 Appendix Heat Recovery 230V REYQ72 96 120PTJU 3D058639A ...
Page 496: ...SiUS34 801A_b Piping Diagrams Appendix 481 Heat Recovery 230V REYQ144PTJU 3D058640 ...
Page 497: ...Piping Diagrams SiUS34 801A_b 482 Appendix Heat Recovery 230V REMQ72PTJU 3D058637A ...
Page 498: ...SiUS34 801A_b Piping Diagrams Appendix 483 Heat Recovery 230V REMQ96 120PTJU 3D058638A ...
Page 501: ...Piping Diagrams SiUS34 801A_b 486 Appendix 1 3 BS Unit 4D057985A ...
Page 537: ...Piping Installation Point SiUS34 801A_b 522 Appendix ...
Page 543: ...Pressure Sensor SiUS34 801A_b 528 Appendix ...
Page 563: ...SiUS34 801A_b iv Index ...