Set Appliance State:
Set Multimeter to AC Voltage 
Turn Hot Water Tap On
Isolate Mains Power to appliance as per TOPs P4
Selector Switch in DHW position
Selector Switch in DHW position
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Allow fan boiler to commence its ignition sequence.
Check for voltage across connector marked J3 connection 2 (brown wire) and connector J1 connection marked N (blue wire) on power board.
Note:
Correct voltage will only be present during ignition sequence lockout will occur after approximately 10 seconds.
If lock out occurs then boiler will have to be reset.
Check for voltage across connector marked J3 connection 2 (brown wire) and connector J1 connection marked N (blue wire) on power board.
Note:
Correct voltage will only be present during ignition sequence lockout will occur after approximately 10 seconds.
If lock out occurs then boiler will have to be reset.
Isolate as per TOPs P4
and refit as necessary