innovair Inverter FLEX24 DEV24H2R18, Service Manual

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SERVICE MANUAL
Please refer to the IPM checking method in the section of troubleshooting.
B ． On condition that the unit cannot be started up
Step 1:
Cut off the power supply and detach the cover of the wiring box of the compressor. Check the wiring of the
compressor.
Step 2:
Check the resistance between the wiring terminals (U, V, W) of compressor.
Refer to the following table for the resistance between any two terminals:
Compressor model UV Winding resistance VW Winding resistance WU Winding resistance
QXFT-F310zN450
0.79±7% Ω 0.79±7% Ω 0.79±7% Ω
QXAU-F516zX440A
Measure the earth resistance of each wiring terminal. The resistance should be above 10 megohm. If not, we
can judge that the compressor is faulted inside.
Step 3:
On condition that the unit cannot be started up, we also need to check the solenoid valve assembly of the
system, including the electronic expansion valve. The checking method is the same as instructed above.
Step 4:
Check whether the IPM module is normal. Please refer to the IPM checking method in the section of
troubleshooting.
4.4.2.2 Replacement of compressor
Step 1: Preparation
(1) Prepare the components for replacement
When carrying the old and new compressors, do not place the compressors horizontally or upside down. The
angle of inclination should be within ±30°. Make sure the lubricant inside the compressors will not flow from the oil