Service
33
Medium UPM
10
Fault finding
Fault Cause Remedy
1. Pump is not running. No
power supply.
• System is switched off. Check the system controller.
• A fuse in the installation is blown. Replace the fuse.
• The circuit breaker has tripped.
Check the power connection and switch on the circuit
breaker.
• Power supply failure. Check the power supply.
2. Pump is not running. Normal
power supply.
• Controller is switched off. Check the controller and its settings.
• Pump is blocked by impurities.
Remove impurities. Unscrew the deblocking screw at the
front of the pump. Deblock the pump from the front of the
control box with a screwdriver. Be aware of splashing hot
water.
• Pump is defective. Replace the pump.
3. Pump runs at maximum
speed and cannot be
controlled.
• No signal from signal cable.
Check if the cable is connected to the controller. If it is,
replace the cable.
4. Noise in the system. • There is air in the system. Vent the system.
• Differential pressure is too high.
Reduce the pump performance at the pump or external
controller.
5. Noise in the pump. • There is air in the pump. Let the pump run. The pump vents itself over time.
• Inlet pressure is too low.
Increase the system pressure or check the air volume in
the expansion tank, if installed.
6. Insufficient flow. • Pump performance is too low. Check the external controller and the pump settings.
• Hydraulic system is closed or system pressure is
insufficient.
Check the non-return valve and filter. Increase the
system pressure.