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Refrigerant Circuit
SiUS39-602
26
Refirgerant Circuit
1.
Refrigerant Circuit
1.1
REYQ72M, 96M
No. in
refrigerant
system
diagram
Symbol
Name
Major Function
A
M1C
Inverter compressor (INV)
Inverter compressor is operated on frequencies between 52 Hz and 210 Hz
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.
REYQ96M : 29 steps
B
M2C
Standard compressor 1(STD1)
D
M1F
Inverter fan
Since the system is of air heat exchanging type, the fan is operated at 8-step
rotation speed by using the inverter.
E
Y1E
Electronic expansion valve (Main: EV1)
Conducts PI control to make the outlet superheat degree constant when the
air heat exchanger is used at the evaporating side during heating operation
and cooling/heating simultaneous operation.
F
Y2E
Electronic expansion valve (Sub: EV2)
G
Y3E
Electronic expansion valve (Subcool:
EV3)
PI control is applied to keep the outlet superheated degree of sub-cooling
heat exchanger constant.
H
Y1S
Solenoid valve (Hot gas: SVP)
Used to prevent the low pressure from transient falling.
I
Y2S
Solenoid valve (Oil equalization: SVO)
Used for oil equalizing among outdoor units in multiple-outdoor-unit system.
J
Y3S
Solenoid valve (Receiver gas charging:
SVL)
Used to maintain high pressure while in cooling operation at low outdoor
temperature.
K
Y4S
Solenoid valve (Receiver gas discharging: SVG) Used to collect refrigerant to receiver when the 4 way valve changes over.
L
Y5S
Solenoid valve (Discharge gas pipe
closing: SVR)
Used to change the discharge gas pipe to high pressure high temperature gas
line during heating operation and cooling/heating simultaneous operation.
M
Y6S
Solenoid valve (Non-operating unit
liquid pipe closing: SVSL)
Used to open the liquid line to outdoor unit during heating and cooling/
heating simultaneous operation mode C.
N
Y7S
Solenoid valve (High pressure gas pipe
pressure reduction: SVC)
Used to change the discharge gas pipe to low pressure suction gas line
during cooling operation. And also used to equalize high and low pressure
by opening SVC during pressure equalizing control.
O
Y8S
4-way selector valve (Main: 20S1)
Changes the main air heat exchanger into condenser or evaporator.
P
Y9S
4-way selector valve (Sub: 20S2)
Changes the sub air heat exchanger into condenser or evaporator.
Q
S1NPH High pressure sensor
Used to detect high pressure.
R
S2NPL Low pressure sensor
Used to detect low pressure.
S
S1PH
HP pressure switch (For INV
compressor)
In order to prevent the increase of high pressure when a malfunction occurs,
this switch is activated at high pressure of 550 psi or more to stop the
compressor operation.
T
S2PH
HP pressure switch (For STD
compressor 1)
V
–
Fusible plug
In order to prevent the increase of pressure when abnormal heating is caused
by fire or others, the fusible part of the plug is molten at a temperature of 158
to 167°F to release the pressure into the atmosphere.
W
–
Pressure regulating valve 1 (Receiver to
discharge pipe)
This valve opens at a pressure of 290 to 390 psi or more for prevention of
pressure increase, thus resulting in no damage of functional parts due to the
increase of pressure in transportation or storage.
X
–
Pressure regulating valve 2 (Liquid pipe
to receiver)
Y
–
Pressure regulating valve 3 (Oil
equalizing pipe to discharge pipe)
Z
–
Pressure regulating valve 4 (Discharge
to discharge pipe)
1
R1T
Thermistor (Outdoor air: Ta)
Used to detect outdoor temperature, correct discharge pipe temperature,
and others.
2
R2T
Thermistor (Suction pipe: Ts)
Used to detect suction pipe temperature, keep the suction superheated
degree constant in heating operation, and others.
3
R31T
Thermistor (INV discharge pipe: Tdi)
Used to detect discharge pipe temperature, make the temperature protection
control of compressor, and others.
4
R32T
Thermistor (STD1 discharge pipe: Tds1)
6
R4T
Thermistor (Heat exchanger deicer: Tb)
Used to detect liquid pipe temperature of air heat exchanger, determine
defrosting operation, and others.
7
R5T
Thermistor (Sub-cooling heat
exchanger gas pipe: Tsh)
Used to detect gas pipe temperature on the evaporation side of sub-cooling
heat exchanger, keep the superheated degree at the outlet of sub-cooling
heat exchanger constant, and others.
8
R6T
Thermistor (Receiver outlet liquid pipe:
Tl)
Used to detect receiver outlet liquid pipe temperature, prevent the drift
between outdoor units while in heating operation in the case of multiple-
outdoor-unit system, and others.
9
R7T
Thermistor (Oil equalizing pipe: To)
Used to detect oil equalizing pipe temperature, opening/closing of the oil
equalizing pipe stop valve, and others.
10
R81T
Thermistor (Main heat exchanger gas
pipe: Tg1)
Detects the gas pipe temperature of the main air heat exchanger. Used for the control
making the outlet superheat degree of main air heat exchanger constant, etc.
11
R82T
Thermistor (Sub heat exchanger gas
pipe: Tg2)
Detects the gas pipe temperature of the sub air heat exchanger. Used for the
control making the outlet superheat degree of sub air heat exchanger
constant, etc.
Summary of Contents for REYQ72
Page 35: ...Specifications SiUS39 602 24 Specifications...
Page 121: ...Field Setting SiUS39 602 110 Test Operation...
Page 129: ...Troubleshooting by Remote Controller SiUS39 602 118 Troubleshooting...
Page 225: ...Troubleshooting OP Unified ON OFF Controller SiUS39 602 214 Troubleshooting...
Page 232: ...SiUS39 602 Piping Diagrams Appendix 221 1 3 BS Unit BSVQ36MVJU BSVQ60MVJU 4D045338...
Page 235: ...Wiring Diagrams for Reference SiUS39 602 224 Appendix REYQ144 168 192MTJU C 3D050354A...
Page 240: ...SiUS39 602 Wiring Diagrams for Reference Appendix 229 2 4 BS Unit BSVQ36M 60MVJU 3D045069A...
Page 249: ...Example of Connection R 410A Type SiUS39 602 238 Appendix...
Page 255: ...Method of Replacing The Inverter s Power Transistors and Diode Modules SiUS39 602 244 Appendix...
Page 265: ...Precautions for New Refrigerant R 410A SiUS39 602 254 Precautions for New Refrigerant R 410A...
Page 269: ...SiUS39 602 iv Index...