Set Appliance State:

Gas Off
Isolate Mains Power to appliance as per TOPs P4
CH Demand
Remove spark leads from control box
With the aid of a crocodile clip hold the spark leads in place
close to the control box as shown
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Reset appliance if necessary, press and hold reset button
for 5 seconds, then release.
Allow boiler to commence its ignition sequence.
.... CAUTION. Stand away from boiler.
Does sparking occur for approximately 4 seconds?
Note:
Lockout may occur after 5 attempts to ignite. If lockout occurs,
reset boiler as required to complete test.