Wellea Monobloc
82
Figure 4-4.1: Replacing an inverter module
Paint a layer of thermally conductive
silica gel on the PFC module
Paint a layer of thermally conductive
silica gel on the IPM module
Situation 2: L0 or L4 error appears immediately after the compressor starts up
L0 / L4
U V W wire between inverter module and
compressor is not connected properly
1
Yes
Ensure U V W wire is connected properly
No
Inverter module is damaged
2
Yes
Replace the inverter module
3
No
Compressor has malfunctioned
4
Yes
Replace the compressor
No
Replace the refrigerant system main PCB
Notes:
1.
Connect the U V W wire from the inverter module to the correct compressor terminals, as indicated by the labels on the compressor.
2.
Measure the resistance between each of U, V and W and each of P and N on the inverter module. All the resistances should be infinite. If any of them are
not infinite, the inverter module is damaged and should be replaced. Refer to
Figure 4-2.3 or 4-2.5 in Part 4, 2.3 “Main PCBs for Refrigerant System,
Inverter Module and Filter Boards”.
3.
When replacing an inverter module, a layer of thermally conductive silica gel should be painted on the PFC and IPM modules (on the reverse side of the
inverter module PCB). Refer to Figure 4-4.1.
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.
