Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to DC Volts 
Turn Hot Water Tap On
Gain access to PCB (use Insulation Mat as required)
Remove electrical connector from fan assembly and make safe
Remove electrical connector from fan assembly and make safe
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Reset appliance if required.
(Press reset button once then release)
When the boiler has recognised a DHW demand (tap symbol on display) measure the DC voltage between pin 7 on connector X2 and a suitable earth.
Expect approximately 21vdc.
Is the voltage measured as expected?
(Press reset button once then release)
When the boiler has recognised a DHW demand (tap symbol on display) measure the DC voltage between pin 7 on connector X2 and a suitable earth.
Expect approximately 21vdc.
Is the voltage measured as expected?
Isolate as per TOPs P4
and refit as necessary