Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to AC Volts Set meter to measure AC Volts
DHW Demand
Remove the cover from the pump
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Measurement:

Measure the AC voltage across the Live (marked L) and Neutral (marked N) terminal at the pump.
Expect mains voltage.
Replace the cover after test.