Set Appliance State:

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

Observation:

If required reset boiler.
Allow ignition sequence to commence.
Sparking should occur approximately 6 seconds after fan has started with a duration of approximately 5 seconds then repeated after approximately 30 seconds.
Can sparking be seen at the electrode tip?
Note.
Electrode tip can be observed through window next to ignition electrode, 5 attempts of ignition will occur before lockout, reset boiler as required