Set Appliance State:
Gas Off
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to DC Volts 
CH Demand
Gain access to PCB (use Insulation Mat as required)
Remove electrical connector to spark generator and make safe
Remove electrical connector to spark generator and make safe
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Reset appliance if required.
(press and hold the reset button for 4 seconds then release)
Measure for DC voltage across brown lead on connector X21 and an earth (use the copper pipe to the gas valve as earth).
Approximately 85 Vdc should be present, as the appliance goes through its ignition cycle the voltage should increase to approximately 365 Vdc as the PCB sends power to the spark generator then return to 85 Vdc before the next ignition attempt.
Does the voltage behave as described above?
(press and hold the reset button for 4 seconds then release)
Measure for DC voltage across brown lead on connector X21 and an earth (use the copper pipe to the gas valve as earth).
Approximately 85 Vdc should be present, as the appliance goes through its ignition cycle the voltage should increase to approximately 365 Vdc as the PCB sends power to the spark generator then return to 85 Vdc before the next ignition attempt.
Does the voltage behave as described above?
Isolate as per TOPs P4
and refit as necessary