Set Appliance State:

Mains Power Off
Turn Hot Water Tap On
DHW temperature control to maximum
CH temperature control to minimum
WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure
Mains Power On

Measurement:

Test 1:
Test between Pin 10 (Live in) and a suitable Earth.
Expect mains voltage.
Test 2:
Test between Pin 11 (Neutral in) and a suitable Earth.
Expect approximately 15V AC or less.