Ipm Protection - Haier HSU-18HEA03/R2(DB)-I Service Manual

7.3.4 IPM protection

outdoor display LED1 flash 2 times:
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
Causes
Troubleshooting * Caution Be sure to turn off power switch before connect or disconnect connector,
Turn off the power.check if the
compressor wiring connect.
Check the IPM module
Normal?
Test the resistance values among
Phases U, V and W of compressor
If the resistance are
equal or less than 3
Check the installation
condition.
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, to measure resistance between P (+) andN (-) 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(+)terminal of
tester)
Normal resistance
Unacceptable resistance
HSU-18HEA03/R2(DB)-I
IPM protection dues to the compressor faulty
IPM protection dues to faulty PCB of IPM module
Compressor wiring disconnected
else parts damage may be occurred.
Yes
NO
Yes
Yes
tester(P(+)for digital
tester(N(-)for digital
NO
Renewedly connect the wiring
Change the IPM module
NO
P(+) UVW
UVW P(+)
Several k to several M ( )
Short (0 ) or open
63
Service Diagnosis
Replace the compressor
P(-) UVW
UVW P(-)
Domestic air conditioner
or