Outdoor Unit Fan Troubleshooting - Mitsubishi Electric PUHY-P200 Service Handbook

[ IX Troubleshooting ]
(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 (2-way valve) , SV5c (2-way valve) (only for P350-P450, EP250, and EP300 models)
This solenoid valve is a switching valve that closes 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.
Outdoor Unit Fan
-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."(page 288) and IX [4] -6- (2) [6] "Check the Fan board failure."(page 288)
(2) Electromagnetic contactor (52F)(P450, EP300 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
Cooling
Heating
Defrost
HWE10040
SW1
ON
No. of outdoor unit fans
1
(Left:Controller side)
1
(Left:Controller side)
2
2
0
1 2 3 4 5 6 7 8 9 10
4-way valve 2-way valve
21S4a OFF SV5b
21S4b OFF SV5c
21S4c ON
21S4a OFF SV5b
21S4b ON SV5c
21S4c ON
21S4a OFF SV5b
21S4b OFF SV5c
21S4c OFF
21S4a ON SV5b
21S4b ON SV5c
21S4c ON
21S4a OFF SV5b
21S4b OFF SV5c
21S4c OFF
- 277 -
52F
OFF
ON OFF
ON
ON OFF
OFF
OFF ON
OFF
OFF ON
OFF
OFF OFF
GB