38MARB: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
43
DIAGNOSIS AND SOLUTION (CONT)
Top temperature protection for compressor or High temperature or High pressure protection of IPM
module (PC02)
Description:
For some models with overload protection, if the sampling voltage is not 5V, the LED displays the failure. If the IPM module
temperature is higher than a certain value, the LED displays the failure code. For some models with a high pressure switch, the outdoor pressure switch
cuts off the system when the pressure is higher than 4.4 MPa and the LED displays the failure code
.
Recommended parts to repair:
• Connection wires
• Outdoor PCB
• IPM module board
• High pressure protector
• System blockages
Troubleshooting
NOTE:
For certain models, the outdoor PCB can not be removed separately. In this case, the outdoor electric control box should be replaced as a
whole.
Check if the air flow system
of the indoor and outdoor units
are obstructed.
Clear up the air inlet and outlet or the indoor
and outdoor heat exchangers.
Yes
No
Yes
Yes
Turn off the power supply.
Wait 10 minutes and turn back on.
Check if the compressor top
temperature is more than 90°C?
No
Check if the refrigerant
system is normal.
Repair the refrigerant
system
Replace the outdoor control PCB.
Yes
Check if all the connections, especially
the OLP (Over Load Protector) connection
sensor, is good.
Correct the connection.
No
Measure the resistance
between the two O L P ports.
Is it zero?
Yes
Replace the OLP.
No
Replace the outdoor control PCB.
Yes
No
Check the fastening screws on the
PCB and IPM radiator.
Are they
fixed tightly?
Replace the outdoor
control PCB.
Tighten the screws and apply
silicon grease.
NO
YES
