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SiUS34-801A_b
Troubleshooting (OP: Unified ON/OFF Controller)
Troubleshooting
467
[Check 10] Check for causes of wet operation.
Referring to the Fault Tree Analysis (FTA) shown below, identify faulty points.
Refrigerant accumulation
Overcharge of refrigerant
Faulty crankcase heater
Frequent ON/OFF of compressor
[Cooling]
Indoor unit
motorized valve
opens too
much. (*1)
[Heating]
Outdoor unit
motorized valve
opens too
much. (*2)
Faulty control
of superheated
degree
Faulty indoor
unit motorized
valve
Faulty outdoor
unit motorized
valve
Faulty control
Faulty control
Faulty valve coil
Faulty control PC board
Faulty valve body
Faulty valve coil
Faulty valve body
Faulty power pressure sensor
Faulty suction pipe thermistor
Faulty control PC board
Faulty indoor unit
gas pipe thermistor
Faulty indoor unit
liquid pipe thermistor
←
Refer to information in the [Check 6]
section.
←
Does the valve coil have normal
resistance and insulation?
(Refer to information in the [Check 11]
section.)
←
Is the connector correctly connected?
Are the thermistor resistance
characteristics normal?
←
Is the connector correctly connected?
Are the thermistor resistance
characteristics normal?
←
Does the valve coil have normal
resistance and insulation?
(Refer to information in the [Check 11]
section.)
←
Are the voltage characteristics normal?
←
Is the connector correctly connected?
Does the thermistor have normal
resistance characteristics?
←
Is the pressure reading of the service
checker corresponding to the actual
measurement of the sensor?
←
Can the fan motor be rotated by
hand?
Does the fan motor coil have
normal resistance and
insulation?
←
Does the air filter get clogged?
←
Are there any obstacles in the air
passage?
Wet operation
Degraded
evaporation
capacity
Increased
resistance
in air
passage
Dirty evaporator
Reduced
air quantity
Reduced
fan output
*1: "Superheated degree control" in cooling operation is exercised with the indoor unit motorized valve.
*2: "Superheated degree control" in heating operation is exercised with the outdoor unit motorized valve (EV1).
(Refer to information on P47, 195.)
*3: Guideline of superheated degree to judge as wet operation
Suction gas superheated degree: Not more than 5.4
°
F;
Discharge gas superheated degree: Not more than
27
°
F, except immediately after compressor starts up or is running under drooping control.
(Use the values shown above as a guideline. Even if the superheated degree falls in the range, the compressor
may be normal depending on other conditions.)
Faulty fan motor
Dirty filter
Obstacles
Faulty control PC board
(including faulty
capacity setting)
←
Does the heat exchanger get clogged?
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 ...