Cause
•
The pump inlet pressure is too low.
•
The inlet pipe is partly blocked by impurities.
•
The non-return valve is blocked in a closed
position.
•
There is a leakage in the inlet pipe.
•
There is air in the inlet pipe or pump.
10.4 The performance is unstable and there is a green indicator light
Cause
•
The pump inlet pressure is too low.
•
The inlet pipe is partly blocked by impurities.
•
There is a leakage in the inlet pipe.
•
There is air in the inlet pipe.
10.5 The pump is not running and the motor shows a red indicator light
Cause
The motor is overheated.
The sensor is defective.
Cause unknown.
Remedy
•
Check the inlet conditions of the pump.
•
Remove and clean the inlet pipe.
•
Inspect, repair, or replace the non-return valve if
necessary.
•
Vent the inlet pipe and the pump.
Remedy
•
Check the inlet conditions of the pump.
•
Remove and clean the inlet pipe.
•
Remove and repair the inlet pipe.
•
Vent the inlet pipe and the pump.
Remedy
•
Check the inlet conditions of the pump.
•
Remove and clean the inlet pipe.
•
Remove and repair the inlet pipe.
•
Vent the inlet pipe and the pump.
•
Replace the sensor.
•
Contact Grundfos or an authorized service
workshop.
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