Daikin VRV S RXQ4/5ARV1 - Check; High Pressure Check

SiAF332111E Check
Part 6 Service Diagnosis 337
Note(s)
Reference
6. Check
6.1 High Pressure Check
CHECK 1 Referring to the Fault Tree Analysis (FTA) shown below, probe the defective points.
CHECK 6 Refer to page 345.
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:
(1)
Defective outdoor
unit electronic
expansion valve
Defective valve coil
Defective 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.
Defective
control
Defective high pressure sensor
Defective outdoor unit main PCB
 Are the electrical characteristics normal?
 Is the pressure value checked with the Service Checker
corresponding to the measurement of the pressure sensor?
Defective
high
pressure
control
In cooling
High suction
air
temperature
of the
condenser
High suction
air temperature
of outdoor unit
Short circuit
High outdoor air temperature
 Is the suction air temperature less than 43C?
 Is the outdoor air temperature less than 43C?
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
Defective fan
motor
Can the fan motor be rotated with hands?
Are the motor coil resistance and
insulation normal?
If a spare PCB is mounted, is the capacity
setting properly made?
Defective outdoor
unit main PCB
(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
Refer to CHECK 6 
1. In cooling, the normal state of the outdoor unit electronic expansion valve (main)
is fully open.