The Pump Supplies Insufficient Flow; The Pump Vibrates And Operates Noisily; The Pump Stops Unexpectedly During Operation And Starts Again After A While; The Pressure Switch Starts And Stops Frequently During Normal Water Delivery - Grundfos JP PS Notice D'installation Et De Fonctionnement

9.7 The pump supplies insufficient flow

Cause
Insufficient intake due to blockage or worn parts
Remedy
• Blocked foot valve. Clean the foot valve.
• The impeller is blocked or worn. Remove the blockage or replace the worn parts.
• The diameter of the intake pipe is insufficient. Replace it with a larger diameter pipe.

9.8 The pump vibrates and operates noisily

Cause
Loose parts or problem with flow
Remedy
• Check that the pump and the pipes are firmly anchored. Tighten or fix the loose parts.
• Cavitation in the pump, that is greater demand than the pump's ability to deliver. Reduce the intake height or check for load losses.
• The pump is running above its intended maximum capacity. Limit the flow at delivery.

9.9 The pump stops unexpectedly during operation and starts again after a while

Cause
Overheating
Remedy
• The thermal switch in the motor has tripped. The motor will restart when it has cooled. If not, check the impeller for blockage. Check
that the ambient temperature is below that stated on the nameplate.
• If you find no blockage or high ambient temperature, then the motor is defective. Replace the product.

9.10 The pressure switch starts and stops frequently during normal water delivery

Cause
Incorrect pressure switch setting
Remedy
• Check the setting of the pressure switch. Increase the setting value incrementally until the problem is resolved. Do not forget to reset
the minimum intervention pressure.
• Ensure that the air charge in the pressure tank is set at 2 psi less than the pressure switch setting while there is no water pressure in
the system.
• The pressure tank diaphragm is broken. Replace the pressure tank.
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