Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Voltage 
CH Demand
Control Thermostat in high position
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Allow the Boiler to sequence its purge period (approximately 10 seconds)
Test 1.
Measure the voltage across connection 1 (Brown wire) and connection 3 (Blue wire) on connector GV1 on the Interconnection Board.
Test 2.
Measure the voltage across connection 2 (Black wire) and connection 3 (Blue wire) on connector GV1.
Note.
Voltage will only be present during spark sequence.
Voltage will cease when Burner fails to ignite.
Test 1.
Measure the voltage across connection 1 (Brown wire) and connection 3 (Blue wire) on connector GV1 on the Interconnection Board.
Test 2.
Measure the voltage across connection 2 (Black wire) and connection 3 (Blue wire) on connector GV1.
Note.
Voltage will only be present during spark sequence.
Voltage will cease when Burner fails to ignite.
Isolate as per TOPs P4
and refit as necessary