Check; High Pressure Check - Daikin RXQ12AHR Service Manual

SiAF341904E

6. Check

6.1

High Pressure Check

CHECK 1 Referring to the Fault Tree Analysis (FTA) shown below, probe the defective points.
Local
pressure
rise
Rise in high
pressure
Defective
high
pressure
control
In cooling
High suction
air
temperature
of the
condenser
Degradation
in condensing
capacity
Excessive refrigerant charging
Reference
CHECK 6 Refer to page 292.
Part 6 Service Diagnosis
Stop valve closed
High pipe
Bent or crushed pipe
resistance
Clogging of foreign
particles
Defective high pressure sensor
Defective
control
Defective outdoor unit main PCB ←Are the voltage characteristics normal?
Short circuit
High suction
air temperature
of outdoor unit High outdoor air temperature
Dirty condenser
Mixing of non-condensable gas
Decreased
fan
Decreased
output
fan airflow
rate
High air
passage
resistance
←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?
←Is the pressure value checked with the Service Checker
corresponding to the measurement of the pressure sensor?
←Is the suction air temperature not more than
43°C?
←Is the outdoor air temperature not more than
43°C?
←Is the heat exchanger clogged? (In cooling)
←Is air or else mixed in the refrigerant system?
Defective fan
←Can the fan motor be rotated with hands?
motor
Are the motor coil resistance and
insulation normal?
Defective outdoor
unit main PCB ←If a spare PCB is mounted, is the capacity
(Including
setting properly made?
capacity setting)
←Is the air filter clogged?
Dirty filter
←Is there any obstacle in the air passage?
Obstacle
← Refer to CHECK 6 .
Check
287