Kaisai 06RY1, Service Manual

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Procedure 4.16.4
P1
High pressure switch connection or
pressure sensor connection on
refrigerant system main PCB is loose
1
Yes
Ensure the pressure switch is connected
properly
No
Pressure sensor has short-circuited or
failed
2
Yes
Replace the pressure sensor
No
The high pressure side is blocked, caused
by crushed or bent pipe or blocked EXV
3
Yes
Inspect the system and fix the error
No
The heat exchange is poor
4
Yes
Inspect the system and fix the error
No
The water flow rate is not sufficient in
cooling mode
5
Yes
Inspect the water system and fix the
error
No
Replace outdoor main PCB
Notes:
1. High pressure switch connection is port CN13 on the KHC -06(08,10)RY1 outdoor unit refrigerant system main PCB (labeled 16 in Figure 4-2.2 in Part4,
2.3 "Main PCB for Refrigerant System, Inverter Module"). port CN13 on the MHA-V12(14,16)W/D2N8-B outdoor unit refrigerant system main PCB
(labeled 16 in Figure 4-2.3 in Part 4, 2. 3 "Main PCB for Refrigerant System, Inverter Module"), port CN31 on the KHC -12(14,16)RY3 outdoor unit
refrigerant system main PCB (labeled 20 in Figure 4-2.4 in Part 4, 2. 3 "Main PCB for Refrigerant System, Inverter Module").
2.
Measure the resistance among the three terminals of the pressure sensor. If the resistance is of the order of mega Ohms or infinite, the pressure
sensor has failed.
3.
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.
4.
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.
5.
Check water pressure on the manometer. If the water pressure is not > 1 bar, water flow is insufficient. Refer to Figure 2-1.2 and 2-1.6 in Part 2, 1
“Layout of Functional Components”.
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4.17 P3 Troubleshooting
Digital display output 4.17.1
Description 4.17.2

Compressor current protection.

When the compressor current rises above the protection value (4/6kW models 18A, 8/10kW model 19A,
12/14/16kW
single phase model 30A, 12/14/16kW three phase model 14A), the system displays P3 protection
and Mono stops running. When the current returns to the normal range, P3 is removed and normal operation
resumes.

Error code is displayed on refrigerant system main control board for refrigerant system and user interface.
Possible causes 4.17.3

Power supply abnormal.

Poor condenser heat exchange.

High pressure side blockage.

Inverter module damaged.

Compressor damaged.

Main PCB damaged.
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