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Basic Control
SiUS39-602
40
Function
2.
Basic Control
2.1
Normal Operation
Cooling Operation
In heating operation, or heating / cooling operation
★
Heating operation is not functional at an outdoor air temperature of 77°F or more.
Actuator
Operation
Remarks
Compressor
Compressor PI control
Used for high pressure control, low pressure
protection control,discharge pipe temperature
protection control, and compressor operating
frequency upper limit control with inverter
protection control.
Outdoor unit fan
Cooling fan control
Four way valve 1 (20S1)
OFF
Four way valve 2 (20S2)
OFF
Main motorized valve (EV1)
1400 pls
Sub motorized valve (EV2)
1400 pls
Sub-cooling motorized valve (EV3)
PI control
(EV3 control)
Hot gas bypass valve (SVP)
Protection control
This valve turns on with low pressure protection
control.
Oil equalization valve (SVO)
Oil level equalizing control
In the case of multi-outdoor-unit system, this valve
repeats ON/OFF operation at regular intervals of
time.
Receiver gas charging valve (SVL)
OFF
This valve turns on when outdoor temperature is
low.
Receiver gas discharge valve (SVG)
ON
Discharge pipe stop valve (SVR)
OFF
Non-operating unit liquid pipe stop valve
(SVSL)
OFF
High pressure gas pipe pressure
reduction valve (SVC)
ON
Actuator
Operation
Remarks
Compressor
Compressor PI control
Used for high pressure control, low pressure
protection control,discharge pipe temperature
protection control, and compressor operating
frequency upper limit control with inverter
protection control.
Outdoor unit fan
Cooling fan control
Four way valve 1 (20S1)
Depend on heat exchanger
mode (heating, simultaneous
cooling / heating operation)
Four way valve 2 (20S2)
Depend on heat exchanger
mode (heating, simultaneous
cooling / heating operation)
Main motorized valve (EV1)
Depend on heat exchanger
mode (heating, simultaneous
cooling / heating operation)
Sub motorized valve (EV2)
Depend on heat exchanger
mode (heating, simultaneous
cooling / heating operation)
Sub-cooling motorized valve (EV3)
PI control
(EV3 control)
Hot gas bypass valve (SVP)
OFF
This valve turns on with low pressure protection
control.
Oil equalization valve (SVO)
Oil level equalizing control
In the case of multi-outdoor-unit system, this valve
repeats ON/OFF operation at regular intervals of
time.
Receiver gas charging valve (SVL)
OFF
This valve turns on when outdoor temperature is
low.
Receiver gas discharge valve (SVG)
ON
Discharge pipe stop valve (SVR)
OFF
Non-operating unit liquid pipe stop valve
(SVSL)
OFF
High pressure gas pipe pressure
reduction valve (SVC)
ON
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...