Set Appliance State:

Mains Reset Switch OFF
Set Multimeter to AC Volts Set meter to measure AC Volts
Isolate Mains Power to appliance as per TOPs P4
Release the front facia by gently prising up the retaining
latches at the top of the facia
Set DHW temperature selector to Off
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Measurement:

Ensure NO demands from external controls
Mains reset switch On.
Measure voltage at terminal 2 (centre connection) on the green terminal block situated on the controls interface PCB and a suitable neutral.
No Mains voltage expected.
Mains power Off.