Inverter PCB Fault / Power Transistor Overheat

What does E51 mean?

The inverter PCB is faulty, or the power transistor module on the inverter has overheated. This indicates a problem with the inverter's control or power section, which drives the compressor, potentially leading to compressor malfunction.

1. 1

   Inspect the inverter PCB for any visible signs of damage, such as burn marks, swollen capacitors, or blown components.

2. 2

   Check the inverter's heatsink for cleanliness and ensure proper airflow; verify inverter cooling fan operation.

3. 3

   Measure compressor current to identify potential overloads contributing to transistor overheat.

4. 4

   Verify voltage supply to the inverter PCB is stable and correct.