Daikin RXQ12AHR Service Manual page 238

Troubleshooting by Error Code
Troubleshooting
232
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Connect the Service Checker.
Mount a pressure gauge on the
high pressure service port.
Reset the operation, and then
restart the operation.
Are the
characteristics of the
suction pipe thermistor
normal?
YES
Are the
discharge pipe
thermistor characteristics
normal?
YES
Are the
high pressure sensor
characteristics
normal?
YES
Service Checker
Use the Service Checker to find indoor units
operating under the following conditions:
• Gas pipe temperature (R6T) - Liquid pipe temperature (R4T) < 2.5˚C
&
• Electronic expansion valve opening < 300 pulse
Stop the relevant indoor units while
the system is in cooling operation,
and then check for the liquid pipe
temperature of these indoor units
after the system is stabilized.
The liquid pipe
temperature is low
(equivalent to the evaporating
temperature).
NO
NO
NO
NO
YES
SiAF341904E
Replace the relevant
thermistor.
Replace the discharge
pipe thermistor.
Replace the high
pressure sensor
(S1NPH).
Replace the indoor
electronic expansion
valve.
Clean the air filters
of the indoor units.
Part 6 Service Diagnosis