Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Voltage 
Boiler Mains Switch ON
Ensure secondary heat exchanger is cool
and there is a demand for Preheat
Ensure secondary heat exchanger is cool
and there is a demand for Preheat
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Apply HW Demand.
Measure voltage across brown lead (live) and pink lead (neutral) at PCB side of inline connector.
Measure voltage across brown lead (live) and pink lead (neutral) at PCB side of inline connector.
Isolate as per TOPs P4
and refit as necessary