innovair Inverter FLEX24 DEV24H2R18, Service Manual

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4.4.3 How to replace the drive module of compressor
Step 1: First, make sure that power is cut off. Set the universal meter at the AC voltage and measure the
voltage between L1, L2, L3, and N. If each time the voltage is 0V (Errors may occur to the universal meter,
sometimes the voltage may not be 0V), proceed with the next step and put a sign on the power switch that reads
“Under maintenance, don’t switch on”.
Step 2: Measure the voltage between DC bus P and N on the drive board of the compressor. Set the
universal meter at the DC voltage and measure the voltage between P and N as shown below. If the voltage is
below 36V, proceed with the next step. In case that a universal meter is not available, disconnect power for 20min
and then continue with the next step.
Step 3: Remove all the wires on the drive board of the compressor.
Step 4: Remove the screws on the drive board of the compressor. The screws are located in the white circles
as shown above in the picture.
Step 5: Replace with a new compressor drive board. Before replacement, apply some silica gel on the IPM
module.
Step 6: Install the new compressor drive board. Fix the screws and connect the wires correctly.
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SERVICE MANUAL