Danfoss Heat Pump Troubleshooting Guide download pdf (Page 5)

5

VMIFB202

Troubleshooting Guide Alarm high pressure

Blocked strainer in the heating system return

Action:

Shut o and clean the strainer on the return row

Air in the heating system, outer jacket or in the Tws coil

Action:

Run the circulation pump in manual mode and listen for air. Switch between hot water and heating modes to check the whole heating

system. Bleed the heating system according to the heat pump installation instructions.

Closed taps or partially closed thermostats/valves in the heating system

Action:

Open any closed taps. Check that the thermostats/valves are open.

The circulation pump is defective or has jammed

Action:

Check that there is there voltage to the circulation pump. If there is no current to the circulation pump, measure at the fuse and the

relay card (See wiring diagram).

If there is current there check the wiring between relay card and circulation pump.

If there is current the circulation pump has jammed.

If this is the case, open the bleed screw and try to release the shaft using a screwdriver for example (Does not apply to the optimum

models). If it still jams, take the drive side apart, clean the drive side using a dish brush and degreaser

Reinstall the motor on the lower connection , ll with water carefully through the upper connection of the pump.

Reinstall the upper connection , open the ball valve, test run the circulation pump in a manual test.

If it is still bad or there is no ow close the ball valves and remove the screws that hold the motor. Check that the paddle wheel is secure

on the shaft.

If the paddle wheel is loose replace the circulation pump.

If the circulation pump does not function or sounds bad after cleaning replace the circulation pump.

Danfoss Heat Pump Troubleshooting Guide Page 5