Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to DC Volts 
Turn Hot Water Tap On
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.
Measure for DC voltage across pin 4 (blue lead) of connector X21 and a suitable earth connection, expect approximately 165 Vdc.
When the fan starts, approximately 310 Vdc should be present for 4 seconds, this will then be present again after approximately 6 seconds - this increase is when sparking would occur.
This will be repeated 5 times before lockout occurs, reset as required until test complete.
Does the voltage behave as described above?
Measure for DC voltage across pin 4 (blue lead) of connector X21 and a suitable earth connection, expect approximately 165 Vdc.
When the fan starts, approximately 310 Vdc should be present for 4 seconds, this will then be present again after approximately 6 seconds - this increase is when sparking would occur.
This will be repeated 5 times before lockout occurs, reset as required until test complete.
Does the voltage behave as described above?
Isolate as per TOPs P4
and refit as necessary