Kaisai 06RY1, Service Manual

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M thermal Mono
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Procedure 4.17.4
P3
The power supply is abnormal
Yes
Check the power supply equipment
No
The condenser heat exchange is poor
1
Yes
Inspect the system and fix the error
No
The high pressure side is blocked, caused
by crushed or bent pipe or blocked EXV
2
Yes
Inspect the system and fix the error
No
Inverter module has short-circuited
3
Yes
Replace the inverter module
No
Compressor has malfunctioned
4
Yes
Replace the compressor
No
Replace outdoor main PCB
Notes:
1. In heating mode check water side heat exchanger, water piping, circulator pumps and water flow switch for dirt/blockages. In cooling mode check air side
heat exchanger, fan(s) and air outlets for dirt/blockages.
2. High pressure side blockage causes discharge temperature to be higher than normal, discharge pressure to be higher than normal and suction pressure to
be lower than normal.
3. Set a multi-meter to buzzer mode and test any two terminals of P N and U V W of the inverter module. If the buzzer sounds, the inverter module has
short-circuited.
4. The normal resistances of the inverter compressor are 0.7- 1.5Ω among U V W and infinite between each of U V W and ground. If any of the resistances
differ from these specifications, the compressor has malfunctioned.
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M thermal Mono
202008 79
4.18 P4 Troubleshooting
Digital display output 4.18.1
Description 4.18.2

Discharge temperature protection.

When the compressor the discharge temperature rises above 115°C, the system displays P4 protection and Mono
stops running. When the discharge temperature falls below 95°C , P4 is removed and normal operation
resumes.

Error code is displayed on refrigerant system main control board for refrigerant system and user interface.
Possible causes 4.18.3

Temperature sensor error

High pressure side blockage.

Poor condenser heat exchange.

Main PCB damaged.
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