Alarm 64 — Stator winding temperature too high

What does 64 mean?

The temperature inside the motor's stator windings has become excessively high, indicating that the motor is overheating. This fault does not reset automatically.

• Pump overload due to system resistance or blockage.
• Insufficient cooling or ventilation around the pump.
• Internal motor issue or component failure.

Click steps to track your progress.

1. 1

   Switch off the pump and allow it to cool down completely.

2. 2

   Ensure the pump is not operating against a closed valve or in a restricted system that could cause overload.

3. 3

   Check for proper ventilation around the pump's control box, and ensure it is not insulated or covered.

4. 4

   If the alarm recurs, further diagnosis may be needed, or contact GRUNDFOS SERVICE for assistance.