Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Voltage 
CH Demand
Gain access to PCB (use Insulation Mat as required)
ON/OFF switch in ON position
CH temp selector to MAX
DHW temp selector to MIN
ON/OFF switch in ON position
CH temp selector to MAX
DHW temp selector to MIN
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Allow the ignition sequence to commence.
Measure voltage at the PCB at connector X13, between the fan live (brown lead) and fan neutral (blue lead) connections.
Mains voltage should be present.
Measure voltage at the PCB at connector X13, between the fan live (brown lead) and fan neutral (blue lead) connections.
Mains voltage should be present.
Isolate as per TOPs P4
and refit as necessary