Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
CH Demand
Main On/Off Control in the On position
Heating Control to Heating & Hot Water
CH Temperature Control to Maximum
Remove side cover from Pump
Remove Yellow plug X12 from Motherboard and make safe
Heating Control to Heating & Hot Water
CH Temperature Control to Maximum
Remove side cover from Pump
Remove Yellow plug X12 from Motherboard and make safe
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
If a fault code is displayed press boiler 'Reset' button.
Measure Mains Voltage across L and N of Pump.
Measure Mains Voltage across L and N of Pump.

Isolate as per TOPs P4
and refit as necessary