Set Appliance State:
Gas Off
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Volts 
Turn Hot Water Tap On
Selector switch set to CH/DHW position
Boiler DHW thermostat set to MAX
Gain access to fan - right hand side panel may require removal
Boiler DHW thermostat set to MAX
Gain access to fan - right hand side panel may require removal
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Measure the AC voltage between the brown (Live)
and blue (Neutral) terminals on the fan.
Expect mains voltage.
and blue (Neutral) terminals on the fan.
Expect mains voltage.
Isolate as per TOPs P4
and refit as necessary