Haier HSU24VHG(DB)-G&W, Service Manual

Page: 55 / 98

Service Diagnosis
54
Domestic Air Conditioner
7.3.4 IPM protection
Outdoor display LED1 flash 2 times. Indoor Display F1
Method of IPM protection is detected by checking the compressor running condition and so on.
Malfunction
Detection
Malfunction The system leads to IPM protection due to over current.
Decision The compressor faulty leads to IPM protection.
Conditions Circuit component of IPM is broken and led to IPM protection.
Supposed IPM protection dues to the compressor faulty.
Causes IPM protection dues to faulty PCB of IPM module.
Compressor wiring disconnected.
Troubleshooting * Caution Be sure to turn off power switch before connect or disconnect connector, or
else parts damage may be occurred.
Check the IPM module method:
Disconnect the compressor harness connector from the outdoor unit PCB.
To disengage the connector, press the protrusion on the connector.
Then, measure resistance between P (+) and N (-) and the U, V and W terminals of the compressor
connector with a multi-tester. Evaluate the measurement results for a pass/fail judgment.
N(-)terminal of tester(P(+)for digital
tester) P(+) UVW P(-) UVW
P(+)terminal of tester(N(-)for digital
tester) UVW P(+) UVW P(-)
Normal resistance
Several kΩ to several MΩ (
и
)
Unacceptable resistance Short (0 Ω) or open
Yes
Turn off the power. check if
the compressor wiring
connected ok or not
NO
Check the IPM module
Normal?
Yes
NO
Test the resistance values among
Phases U, V and W of compressor
If the resistance is 1Ω
or so
NO
Yes
Check the installation condition.
Change the IPM module
Disconnect the wiring
Replace the compressor