Set Appliance State:
On/Off Switch OFF
Set Multimeter to AC Volts 
CH Demand
Isolate Mains Power to appliance as per TOPs P4
CH temperature control set to maximum
CH temperature control set to maximum
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Appliance On/Off control set to On position.
Measure the voltage at ST15 live (brown wire) and a suitable neutral.
Measure the voltage at ST15 live (brown wire) and a suitable neutral.
Isolate as per TOPs P4
and refit as necessary