Set Appliance State:

Mains Power Off
Wait approximately 15 seconds
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

After following the above procedure has the fault reset?
If the fault code has reset but the boiler now shows a different fault CLICK HERE
If the "Too many Restarts" fault cannot be reset CLICK HERE
If the fault resets but you would like to confirm the operation of the boiler CLICK HERE