Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Volts 
CH Demand
CH temperature control to max
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.
Measure for A/C voltage across resistor R115 (as illustrated) and a suitable earth connection.
Allow boiler to start ignition sequence, does the voltage measured reduce to approximately 88 volts A/C when the burner is heard to ignite?
Note.
1. The burner may only ignite for a few seconds, then ignition starts again.
2. The boiler will go to ignition lockout (3 red flashes) after 5 attempts to ignite, reset boiler as required.
Measure for A/C voltage across resistor R115 (as illustrated) and a suitable earth connection.
Allow boiler to start ignition sequence, does the voltage measured reduce to approximately 88 volts A/C when the burner is heard to ignite?
Note.
1. The burner may only ignite for a few seconds, then ignition starts again.
2. The boiler will go to ignition lockout (3 red flashes) after 5 attempts to ignite, reset boiler as required.
Isolate as per TOPs P4
and refit as necessary