Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
CH Demand
Attach a temperature clamp on the CH flow pipe as near as possible to the appliance
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Allow the boiler to run with a CH demand.
The appliance should run to an operating temperature of approximately 80°C and then the burner should shut down without the overheat LED illuminating.
Does the boiler operate as described?