Daikin VRV RXYQ72-384XAYCA Service Manual page 305

SiUS342004EB
Troubleshooting
Part 6 Service Diagnosis
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 (R10T) and the
compressor suction
thermistor (R12T)
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 – Liquid pipe temperature < 2.5°C (4.5°F)
&
• Electronic expansion valve opening < 300 pulses
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
Troubleshooting by Error Code
Replace the relevant
thermistor.
Replace the discharge
pipe thermistor.
Replace the high
pressure sensor
(S1NPH).
Replace the indoor
unit electronic
expansion valve.
Clean the air filters
of the indoor units.
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