Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Volts 
CH Demand
Gain access to PCB (use Insulation Mat as required)
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Reset boiler if required.
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.
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.
Isolate as per TOPs P4
and refit as necessary