Set Appliance State:
Gas On; Pilot On
Set Multimeter to AC Volts 
Isolate Mains Power to appliance as per TOPs P4
Boiler ON
Selector Lever RIGHT - CH/HW Position
System calling for Heat
Clock On
Boiler ON
Selector Lever RIGHT - CH/HW Position
System calling for Heat
Clock On
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Measure voltage between A9 (Live) and
A12 (Neutral) on PCB, track-side, middle right.
A12 (Neutral) on PCB, track-side, middle right.
Isolate as per TOPs P4
and refit as necessary