Set Appliance State:

Mains Power Off
Set Boiler Control Thermostat to MAX position
CH Demand
Ensure external controls are calling for heat
WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure
Mains Power On

Observation:

Allow the boiler to fire and run.
Ascertain if the temperature of the flow is less than the maximum temperature setting of the boiler control thermostat.
The Boiler Thermostat on its Maximum setting should give a flow temperature of approximately 82°C.