Set Appliance State:

Mains Power Off
Turn Hot Water Tap On
DHW temperature control set to MAX
Preheat OFF
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Reset boiler if required.
Listen for sparking and observe blue LED on front of boiler.
When a flame is detected a blue LED will illuminate at the top of the display.