Check
SiAF341904E
288
Part 6 Service Diagnosis
Reference
6.2 Low Pressure Check
CHECK 2
Referring to the Fault Tree Analysis (FTA) shown below, probe the defective points.
CHECK 7
Refer to page 293.
Abnormally low
pressure
(Low evaporating
temperature)
Defective
low pressure
control
Defective
compressor
capacity
control
Defective low pressure sensor
←
Are the voltage characteristics normal?
Defective outdoor unit main PCB
←
Is the pressure value checked with the Service Checker
corresponding to the measurement of the pressure sensor?
Defective
low pressure
protection
control
Defective low pressure sensor
←
Are the voltage characteristics normal?
Defective hot gas solenoid valve
←
Are the coil resistance and insulation normal?
Defective outdoor unit main PCB
←
Is the pressure value checked with the Service Checker
corresponding to the measurement of the pressure sensor?
In cooling
If the indoor unit
electronic
expansion valve is
throttled too much:
Defective indoor
unit electronic
expansion valve
Defective valve coil
Defective valve body
←
Are the coil resistance and insulation normal?
Defective
control
Defective gas pipe
thermistor of indoor unit
Defective liquid pipe
thermistor of indoor unit
Defective outdoor unit main PCB
←
Check for the thermistor resistance and connection.
←
Check for the thermistor resistance and connection.
←
Are the voltage characteristics normal?
Low suction
air temperature
of the
evaporator
Low suction air
temperature of
indoor unit
Short circuit
←
Is the suction air temperature not less than 14°C
←
Is the indoor temperature not more than 14°C
Low room temperature
Defective suction air thermistor of indoor unit
←
Is the connector properly connected?
Are the thermistor resistance characteristics normal?
High pipe
resistance
Abnormal piping length
Bent or crushed pipe
Clogging of foreign particles
Stop valve closed
←
Does the piping length fall in the permissible range?
←
Conduct visual checks for pipe conditions.
←
Is there any temperature difference caused before
and after the filter or branch pipe?
←
Check to be sure the stop valve is open.
Less
circulation
quantity of
refrigerant
Degradation
in condensing
capacity
Refrigerant shortage
Moisture choke
←
Eliminate moisture by vacuum operation.
Dirty
evaporator
Decreased
fan airflow
rate
Decreased
fan output
Defective fan motor
←
Can the fan motor be rotated with hands?
Are the motor coil resistance and insulation normal?
←
Is the heat exchanger clogged?
Defective outdoor unit
main PCB (Including
capacity setting)
←
If a spare PCB is mounted, is the capacity
setting properly made?
High airflow
passage
resistance
Dirty filter
←
Is there any obstacle in the air passage?
←
Is the air filter clogged?
Obstacle
Defective electronic
expansion valve
control
←
Refer to
CHECK 7
.
Содержание RXQ12AHR
Страница 267: ...SiAF341904E Troubleshooting by Error Code Part 6 Service Diagnosis 261 Reference CHECK 7 Refer to page 293...
Страница 312: ...SiAF341904E 306 Part 7 Appendix 1 Wiring Diagrams 307 1 1 Outdoor Unit 307 1 2 VRV Indoor Unit 310 Part 7 Appendix...
Страница 313: ...SiAF341904E Wiring Diagrams Part 7 Appendix 307 1 Wiring Diagrams 1 1 Outdoor Unit RXQ6 8 10 12ARY1 3D112175E...
Страница 314: ...Wiring Diagrams SiAF341904E 308 Part 7 Appendix RXQ14ARY1 2D112174G...
Страница 315: ...SiAF341904E Wiring Diagrams Part 7 Appendix 309 RXQ16 18 20ARY1 2D112524F...
Страница 317: ...SiAF341904E Wiring Diagrams Part 7 Appendix 311 1 2 2 Auto Grille Panel BYCQ125EASF for FXFSQ 3D108035...
Страница 319: ...SiAF341904E Wiring Diagrams Part 7 Appendix 313 FXMQ40 50 63 80 100ARV1 3D112427A...
Страница 320: ...Wiring Diagrams SiAF341904E 314 Part 7 Appendix 1 2 4 Wall Mounted Type FXAQ20 25 32PVE FXAQ40 50 63PVER1 C 3D076498B...