Set Appliance State:

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

Observation:

To reset the appliance:
Turn the selector switch from the CH/DHW position to the OFF/Reset position, wait a few seconds then turn the selector switch back to the CH/DHW position.
Apply a DHW demand.
Has the boiler reset?
Note:
It is important to apply a DHW demand after resetting.
BOILER RESETS
BOILER DOES NOT RESET LED REMAINS SOLID RED
BOILER RESETS BUT A DIFFERENT FAULT CODE APPEARS