Check
SiME341909EA
262
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 267.
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
.
Summary of Contents for VRV X RXQ10ARYFK
Page 1: ...Service Manual Cooling Only 50 60 Hz RXQ6 48A N R Series SiME341909EA...
Page 289: ...SiME341909EA Wiring Diagrams Part 7 Appendix 283 RXQ10 12ARYFK 2D124184...
Page 290: ...Wiring Diagrams SiME341909EA 284 Part 7 Appendix RXQ14 16ARYFK 2D124183...
Page 295: ...SiME341909EA Wiring Diagrams Part 7 Appendix 289 FXMQ40 50 63 80 100ARV1 3D127112 04 59...