Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Volts 
Gain access to PCB (use Insulation Mat as required)
Ensure there are No demands from External Controls
Ensure No taps are running
Ensure there are No demands from External Controls
Ensure No taps are running
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Measure for mains voltage at the external controls into the boiler.
Mains voltage should not be present from external controls and no taps should be running i.e. no demands that could cause the boiler to fire.
Mains voltage should not be present from external controls and no taps should be running i.e. no demands that could cause the boiler to fire.
Isolate as per TOPs P4
and refit as necessary