Set Appliance State:
Set Multimeter to AC Volts 
Turn Hot Water Tap On
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Reset boiler if required.
Allow appliance to commence its ignition sequence.
Measure for A/C voltage across the electrical connectors to the spark generator.
Approximately 5 seconds after the fan has started, mains voltage should be measured at the spark generator (see note)?
Note:
Voltage will only be present during the sparking phase of ignition, the appliance will have 3 attempts of ignition before lockout occurs, reset boiler as required.
Allow appliance to commence its ignition sequence.
Measure for A/C voltage across the electrical connectors to the spark generator.
Approximately 5 seconds after the fan has started, mains voltage should be measured at the spark generator (see note)?
Note:
Voltage will only be present during the sparking phase of ignition, the appliance will have 3 attempts of ignition before lockout occurs, reset boiler as required.
Isolate as per TOPs P4
and refit as necessary