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Troubleshooting (OP: Unified ON/OFF Controller)
SiBE37-701
372
Troubleshooting
[CHECK 5] Check for causes of rise in high pressure
Referring to the Fault Tree Analysis (FTA) shown below, probe the faulty points.
Short circuit
Rise in high
pressure
Local
pressure
rise
High pipe
resistance
Stop valve closed
Bent or crashed pipe
Clogging of foreign
particles
←
Check to be sure the stop valve is open.
←
Conduct visual checks for pipe conditions.
←
Is there any temperature difference caused before
and after the filter or branch pipe.
[In cooling]
If the outdoor unit electronic
expansion valve is throttled:
(See *1.)
Faulty outdoor
unit motorized
valve
Faulty valve coil
Faulty valve body
←
Are the coil resistance and insulation normal?
A temperature difference in excess of 10
°
C
between the inlet and the outlet is deemed to be abnormal.
Faulty
control
Faulty high pressure sensor
Faulty control PC board
←
Are the electrical characteristics normal?
←
Is the pressure value checked with the Service Checker
corresponding to the measurement of the pressure sensor?
←
Are the coil resistance and insulation
normal?
Faulty high
pressure
control
Faulty indoor
unit motorized
valve
Faulty valve coil
Faulty valve body
[In heating]
If the indoor unit electronic
expansion valve excessively
throttled:
(See *2.)
Faulty
control
Faulty high pressure sensor
Faulty indoor unit
liquid pipe thermistor
Faulty control PC board
←
Are the electrical characteristics normal?
←
In the connector properly connected?
Are the thermistor resistance characteristics normal?
←
Is the pressure value checked with the Service
Checker corresponding to the measurement of the
pressure sensor?
[In cooling]
High suction
air
temperature
of the
condenser
[In heating]
High suction air
temperature
of outdoor unit
Short circuit
High ambient temperature
←
Is the suction air temperature not more than
43
°
C?
←
Is the outdoor temperature not more than 43
°
C?
High suction
air temperature
of indoor unit
High ambient temperature
←
Is the suction air temperature not more than 27
°
C?
←
Is the indoor temperature not more than 27
°
C?
Faulty suction air thermistor of indoor unit
High suction air temperature of outdoor unit
Faulty outdoor temperature thermistor of outdoor unit
←
Is the connector properly connected?
Are the thermistor resistance characteristics normal?
←
Is the outdoor temperature not more than 16
°
CWB?
←
Is the connector properly connected?
Are the thermistor resistance characteristics normal?
Degradation
in condensing
capacity
Dirty condenser
Mixing of non-condensable gas
←
Is the heat exchanger clogged? (In cooling)
←
Is air or else mixed in the refrigerant system?
Decreased
fan airflow
rate
Decreased
fan
output
Faulty fan
motor
←
Can the fan motor be rotated with hands?
Are the motor coil resistance and
insulation normal?
←
If a spare PC board is mounted, is the
capacity setting properly made?
Faulty control
PC board
(Including
capacity setting)
High air
passage
resistance
Dirty filter
←
Is the air filter clogged?
Obstacle
←
Is there any obstacle in the air passage?
Excessive refrigerant charging
Improper model selection [In heating]
←
←
Is the indoor unit too small compared to
the large-sized outdoor unit?
*1: In cooling, it is normal if the outdoor unit electronic expansion valve (EVM) is fully open.
*2: In heating, the indoor unit electronic expansion valve is used for “subcooled degree control”.
(For details, refer to “Electronic Expansion Valve Control” on P147.)
SDK04009
Summary of Contents for VRV III REYQ8PY1B
Page 1: ...REYQ8 48PY1B R 410A Heat Recovery 50Hz SiBE37 701...
Page 111: ...Refrigerant Flow for Each Operation Mode SiBE37 701 100 Refrigerant Circuit...
Page 252: ...SiBE37 701 Troubleshooting by Remote Controller Troubleshooting 241...
Page 396: ...SiBE37 701 Piping Diagrams Appendix 385 REYQ14P 16P 3D058153B S2NPL S1NPH...
Page 397: ...Piping Diagrams SiBE37 701 386 Appendix REMQ8P 3D057743...
Page 398: ...SiBE37 701 Piping Diagrams Appendix 387 REMQ10P 12P 3D057742...
Page 399: ...Piping Diagrams SiBE37 701 388 Appendix REMQ14P 16P 3D057741...
Page 400: ...SiBE37 701 Piping Diagrams Appendix 389 1 2 Indoor Unit FXFQ P...
Page 405: ...Piping Diagrams SiBE37 701 394 Appendix 1 3 BS Unit 4D057985A...
Page 415: ...Wiring Diagrams for Reference SiBE37 701 404 Appendix FXZQ20M 25M 32M 40M 50MV1...
Page 416: ...SiBE37 701 Wiring Diagrams for Reference Appendix 405 FXCQ20M 25M 32M 63MV3...
Page 417: ...Wiring Diagrams for Reference SiBE37 701 406 Appendix FXCQ40M 50M 80M 125MV3...
Page 420: ...SiBE37 701 Wiring Diagrams for Reference Appendix 409 FXDQ20M 25MV3...
Page 421: ...Wiring Diagrams for Reference SiBE37 701 410 Appendix FXSQ20M 25M 32M 40M 50M 63MV3...
Page 422: ...SiBE37 701 Wiring Diagrams for Reference Appendix 411 FXSQ80M 100M 125MV3...
Page 447: ...Example of connection SiBE37 701 436 Appendix...
Page 453: ...Method of Checking the Inverter s Power Transistors and Diode Modules SiBE37 701 442 Appendix...
Page 467: ...SiBE37 701 iv Index...