Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Volts 
Turn Hot Water Tap On
Gain access to PCB (use Insulation Mat as required)
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Reset appliance if required (press and hold the reset button until the chimney sweep button led flashes rapidly, then release the reset button.
Allow the pump purge to complete.
Measure for AC voltage across resistor R115 (as illustrated) and a suitable earth connection.
Allow appliance to start ignition sequence, does the voltage measured reduce to approximately 88 volts AC when the burner is heard to ignite?
Note.
1. The burner may only ignite for a few secs, then ignition starts again.
2. The appliance will go to ignition lockout (3 red flashes) after 5 attempts to ignite, reset appliance as required.
Allow the pump purge to complete.
Measure for AC voltage across resistor R115 (as illustrated) and a suitable earth connection.
Allow appliance to start ignition sequence, does the voltage measured reduce to approximately 88 volts AC when the burner is heard to ignite?
Note.
1. The burner may only ignite for a few secs, then ignition starts again.
2. The appliance will go to ignition lockout (3 red flashes) after 5 attempts to ignite, reset appliance as required.
Isolate as per TOPs P4
and refit as necessary