Daikin RTSQ20PY1 Service Manual page 305

SiBE31-801_C
Troubleshooting
In cooling mode
In heating mode
Troubleshooting
Be sure to turn off power switch before connect or disconnect connector,
Caution
or parts damage may be occurred.
(1) Set up a pressure gauge at the service port on the low
pressure side.
(2) Reset the operation using the remote controller then restart.
Check if the low
pressure is
0.1MPa or below.
(∗1)
YES
∗1: Check the low pressure value by using pressure gauge in operation.
∗2: Compare the actual measurement value by pressure sensor with the
value by the pressure gauge.
(To gain actual measurement value by pressure sensor, measure the
voltage at the connector [between (2)-(3)] and then convert the value
into pressure referring to P.410.)
Reset the operation using the remote controller then restart.
Check if the temperature
difference between the suction
pipe and the heat exchanger is
20 °C and over.
YES
∗3: Compare the thermistor resistance value with the value on the surface
thermometer.
∗ 1
CHECK 6
: Referring to the information on P.343.
∗ 2
CHECK 3 : Referring to the information on P.340.
Troubleshooting by Indication on the Remote Controller
Check if the
NO
property of low
pressure sensor is
normal. (∗2)
YES
Check if the property of suction
NO
pipe thermistor (A7T) and heat
exchanger thermistor (R4T) are
normal. (*3)
YES
NO
Replace the low pressure
sensor.
Replace the main PCB
(A1P).
Remove the factor of
decreasing low pressure by
referring to .
CHECK 6
∗1
NO
Replace the thermistor.
Replace the main PCB.
Remove the factor of
superheating by referring to
CHECK 3 .
∗2
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