Set Appliance State:
Mains Power Off
Set Multimeter to AC Volts 
Turn Hot Water Tap On
Selector switch set to DHW
Preheat switched OFF
Note.
Slightly move connectors until PCB connection strips
are exposed for voltage measurement
Preheat switched OFF
Note.
Slightly move connectors until PCB connection strips
are exposed for voltage measurement
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Allow appliance to go through it's ignition sequence.
Measure for AC voltage across pin 8 (X3 connector PCB) and
main neutral (terminal block).
Expected voltage will reduce from 120 Vac to approximately 110 Vac or less, when burner has lit (flame detected).
Note.
Appliance may enter lockout during this test, reset as required
until test is complete.
Measure for AC voltage across pin 8 (X3 connector PCB) and
main neutral (terminal block).
Expected voltage will reduce from 120 Vac to approximately 110 Vac or less, when burner has lit (flame detected).
Note.
Appliance may enter lockout during this test, reset as required
until test is complete.
Isolate as per TOPs P4
and refit as necessary