Set Appliance State:

Mains Power Off
CH temperature control to max
ON/OFF switch set to ON position (pushed in)
Ensure NO demands
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Reset boiler, wait 10 seconds after power is reinstated, press and hold reset button for 5 seconds, then release.
Allow the boiler to complete its self check, this will take approximately 60 seconds, the boiler flow temperature should be displayed during this period.
If no display, fault code or other symbol is encountered then choose that option from below.