Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Voltage 
Turn Hot Water Tap On
Attach Red Crocodile Clip to the Red Wire on the Fan
Attach Black Crocodile Clip to the White Wire on the Fan
Selector Switch in DHW Position
Attach Black Crocodile Clip to the White Wire on the Fan
Selector Switch in DHW Position
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Measure the Potential Difference between the Red and White Wires at the Fan Assembly
A constant voltage reading of 35V AC or Greater is expected.
Warning Voltages at the Fan can be up to 310V AC
A constant voltage reading of 35V AC or Greater is expected.
Warning Voltages at the Fan can be up to 310V AC
Isolate as per TOPs P4
and refit as necessary