Set Appliance State:

Mains Power Off
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Press and hold the reset button for 5 seconds then release, does the appliance reset?
Please choose from one of the following options:
Boiler resets, to retest appliance - CLICK HERE
Boiler resets but returns to internal fault code - CLICK HERE
Boiler resets but displays other fault code - CLICK HERE