Module overheating is one of the common malfunctions in frequency converter operation. For Oulu frequency converters, module overheating is displayed as ERR/FU14 on the operation panel. The causes and troubleshooting methods for module overheating are as follows:

1. Ambient temperature too high: Reduce the ambient temperature.

2. Blocked air duct: Clean the air duct.

3. Fan failure: Replace the fan.

4. Damaged module thermistor: Replace the thermistor.

5. Damaged inverter module: Replace the frequency converter module.