Set Appliance State:
Set Multimeter to AC Volts 
CH Demand
Isolate Mains Power to appliance as per TOPs P4
Boiler On/Off Switch On
Gain access to PCB (use insulation mat as necessary)
Boiler On/Off Switch On
Gain access to PCB (use insulation mat as necessary)
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Allow fan to run and ignition sequence to commence.
Measure the voltage at connector CN1 connection 7 (red wire) on the ignition PCB and a suitable neutral.
Once the burner has lit voltage should increase from approximately 0V AC to mains voltage.
Measure the voltage at connector CN1 connection 7 (red wire) on the ignition PCB and a suitable neutral.
Once the burner has lit voltage should increase from approximately 0V AC to mains voltage.
Isolate as per TOPs P4
and refit as necessary