Blocked motor (51) - Pump cannot start due to blockage

What does 51 mean?

The pump's motor is blocked, preventing it from starting. This is an alarm condition that will appear on the Grundfos GO Remote app and prevent normal operation.

• Accumulation of deposits or dirt inside the pump housing.
• Impeller is jammed and cannot rotate freely.

Click steps to track your progress.

1. 1

   Connect to the Grundfos GO Remote app to confirm the 'Blocked motor' alarm (code 51).

2. 2

   Try to remove deposits by lightly tapping on the cast iron pump housing.

3. 3

   If tapping does not resolve the issue, switch off the pump's power supply at the main switch.

4. 4

   Close isolating valves on either side of the pump and safely drain the system to prevent injury from hot liquid or pressure.

5. 5

   Contact Grundfos Service or a qualified specialist to safely remove the pump head and clear any internal deposits.