Kaisai 06RY1, Service Manual

Page: 81 / 114

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Procedure 4.18.4
P4
Discharge pipe temperature sensor
connection on refrigerant system main
PCB is loose
1
Yes
Ensure the temperature sensor is
connected properly
No
Backup electric heater water outlet
temperature sensor connection,
domestic hot water tank temperature
sensor connection or water side heat
exchanger water outlet temperature
sensor connection on hydronic system
main PCB is loose
2
Yes
Ensure the temperature sensor is
connected properly
No
Temperature sensor has short-circuited
or failed
3
Yes
Replace the sensor
No
High pressure switch connection or
pressure sensor connection on
refrigerant system main PCB is loose
4
Yes
Ensure the pressure switch is connected
properly
No
Pressure sensor has short-circuited or
failed
5
Yes
Replace the pressure sensor
No
The high pressure side is blocked, caused
by crushed or bent pipe or blocked EXV
4
Yes
Inspect the system and fix the error
No
The condenser heat exchange is poor in
heating mode
5
Yes
Inspect the system and fix the error
No
The water flow rate is not sufficient in
cooling mode
6
Yes
Inspect the water system and fix the
error
No
Replace outdoor main PCB
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Notes:
1.
Discharge pipe temperature sensor connection is port CN8 on the
KHC -06(08,10)RY1
outdoor unit refrigerant system main PCB (labeled 15 in Figure 4-2.2
in Part4, 2.3 "Main PCB for Refrigerant System, Inverter Module"). port CN4 on the
KHC -12(14,16)RY3
outdoor unit refrigerant system main PCB (labeled
15 in Figure 4-2.4 in Part 4, 2. 3 "Main PCB for Refrigerant System, Inverter Module").
2.
Final outlet water temperature sensor and water side heat exchanger water outlet temperature sensor connections are port CN6 on the hydronic box
main
PCB (labeled 10 in Figure 4-2.1 in Part4, 2.2 "Main PCB for Hydronic System"). Domestic hot water tank temperature sensor connection is port
CN13 on hydronic box main PCB (labeled 13 in Figure 4-2.1 in Part4, 2.2 "Main PCB for Hydronic System").
3.
Measure sensor resistance. If the resistance is too low, the sensor has short-circuited. If the resistance is not consistent with the sensor’s
resistance characteristics table, the sensor has failed. Refer to Part 2, 1 “Layout of Functional Components” and to Table 5-5.1 or 5-5.2 in Part 5, 5.1
“Temperature Sensor Resistance Characteristics”.
4.
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 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").
5.
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.
6.
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.
7.
Check air side heat exchanger, fan and air outlets for dirt/blockages.
8.
Check the water side heat exchanger, water piping, circulator pumps and water flow switch for dirt/blockages.
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