Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Volts 
Gain access to PCB (use Insulation Mat as required)
DHW temperature selector to OFF position
Remove diverter valve head
DHW temperature selector to OFF position
Remove diverter valve head
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Test 1
Open a hot tap and measure the voltage across
connector A8 connection 3 (white wire) and
a suitable earth.
Open a hot tap and measure the voltage across
connector A8 connection 3 (white wire) and
a suitable earth.
Isolate as per TOPs P4
and refit as necessary