58
Wellea Monobloc
4.6.4
Procedure
E5 / E6 / E9 / EA
Temperature sensor connection on
refrigerant system main PCB is loose
1
Yes
Ensure the sensor is connected properly
No
Temperature sensor has short-circuited
or failed
2
Yes
Replace the sensor
No
Replace refrigerant system main PCB
Notes:
1.
Air side heat exchanger refrigerant outlet temperature sensor and outdoor ambient temperature sensor connections are port CN9 on the refrigerant
system main PCB (labeled 12 in Figure 4-2.2 in Part 4, 2.3 “Main PCBs for Refrigerant System, Inverter Modules and Filter Boards”, (labeled 5 in Figure 4-2.4
in Part 4, 2.3 “Main PCBs for Refrigerant System, Inverter Modules and Filter Boards” and labeled 6 in Figure 4-2.6 in Part 4, 2.3 “Main PCBs for Refrigerant
System, Inverter Modules and Filter Boards”). Discharge pipe temperature sensor connection is port CN8 on the refrigerant system main PCBs (labeled 11
in Figure 4-2.2 in Part 4, 2.3 “Main PCBs for Refrigerant System, Inverter Modules and Filter Boards”, (labeled 4 in Figures 4-2.4 in Prat 4, 2.3“Main PCBs for
Refrigerant System, Inverter Modules and Filter Boards” and labelled 5 in Figure 4-2.6 in Part 4, 2.3 “Main PCBs for Refrigerant System, Inverter Modules
and Filter Boards”). Suction pipe temperature sensor connection is port CN1 on the MHC-V5(7,9)W/D2N8 outdoor unit refrigerant system main PCB
(labeled 13 in Figure 4-2.2 in Part 4, 2.3 “Main PCBs for Refrigerant System, Inverter Modules and Filter Boards”), port CN24 on the MHC-V12(14,
16)W/D2N8 outdoor unit refrigerant system main PCB (labeled 2 in Figure 4-2.4 in Part 4, 2.3 “Main PCBs for Refrigerant System, Inverter Modules and
Filter Boards”) and port CN4 on the MHC-V12(14, 16)W/D2RN8 outdoor unit refrigerant system main PCB (labeled 4 in Figure 4-2.6 in Part 4, 2.3 “Main
PCBs for Refrigerant System, Inverter Modules and Filter Boards”).
2.
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 Table 4-5.1, and Table 4-5.2 in Part 4, 5.1 “Temperature Sensor Resistance Characteristics”.
