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[ IX Troubleshooting ]
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HWE09120 GB
(3) In case of SV1a (Bypass valve)
This solenoid valve opens when powered (Relay ON).
1) At compressor start-up, the SV1a turns on for 4 minutes, and the operation can be checked by the self-diagnosis LED display
and the closing sound.
2) To check whether the valve is open or closed, check the change of the SV1a downstream piping temperature while the valve
is being powered.Even when the valve is closed, high-temperature refrigerant flows inside the capillary next to the valve.
(Therefore, temperature of the downstream piping will not be low with the valve closed.)
(4) In the case of SV5b (Solenoid valve) , SV5c (Solenoid valve) (SV5c is present only on the P120 and P144 models.)
This solenoid valve is a switching valve that opens when energized. Proper operation of this valve can be checked on the LED
and by the switching sound. During the cooling mode, SV5b and 21S4b, SV5c and 21S4c, are switched simultaneously, which
may make it difficult to check for proper operation of the SV5b or SV5c by listening for the switching sound. If this is the case,
the temperature before and after SV5b or SV5c can be used to determine if the refrigerant is the pipe.
(5) In the case of SV9 (Solenoid valve)
This solenoid valve is a switching valve that opens when energized. Proper operation of this valve can be checked on the LED
display and by the switching sound.
Do not give an impact from outside, as the outer hull will be deformed leading to the malfunction of the inner valve.
-4- Outdoor Unit Fan
(1) Fan motor
To check the revolution of the fan, check the inverter output state on the self-diagnosis LED, as the inverter on the outdoor
fan controls the revolutions of the fan.
When starting the fan, the fan runs at full speed for 5 seconds.
When setting the DIP SW1 as shown in the figure below, the inverter output [%] will appear. 100% indicates the full speed
and 0% indicates the stopping.
As the revolution of the fan changes under control, at the interphase or when the indoor unit operation capacity is low, the
revolution of the fan may change.
If the fan does not move or it vibrates, Fan board problem or fan motor problem is suspected. Refer to IX [4] -6- (2) [5] "Check
the fan motor ground fault or the winding." and IX [4] -6- (2) [6] "Check the Fan board failure."
(2) Electromagnetic contactor (52F)(P120, P144 only)
If the outdoor unit fan is not operating correctly according to what is specified in the table below, check 52F for short-circuit.
Use the flowchart to identify possible problems.
Check that the right and left connectors for the fan motor are connected to the appropriate connectors in the electromagnetic
contactor.
Operation mode No. of outdoor unit fans 4-way valve 2-way valve 52F
Cooling 21S4a OFF SV5b OFF
1 21S4b OFF SV5c ON OFF
(Left:Controller side) 21S4c ON
21S4a OFF SV5b ON
1 21S4b ON SV5c ON OFF
(Left:Controller side) 21S4c ON
21S4a OFF SV5b OFF
2 21S4b OFF SV5c OFF ON
21S4c OFF
Heating 21S4a ON SV5b OFF
2 21S4b ON SV5c OFF ON
21S4c ON
Defrost 21S4a OFF SV5b OFF
0 21S4b OFF SV5c OFF OFF
21S4c OFF
12345678 9 10
ON
SW1