Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Volts 
Turn Hot Water Tap On
Gain access to PCB (use Insulation Mat as required)
Remove fan driver PCB from the fan assembly & make safe
Remove fan driver PCB from the fan assembly & make safe
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Allow the 4 minute pump purge to complete.
Approximately 10 seconds after DHW demand, measure for AC voltage
between connection C1 on the PCB and a suitable Earth.
Voltage measured will be seen to fluctuate on the multimeter.
The image above is only an example of what a multimeter fluctuating looks like, your multimeter may display different readings.
Does the voltage fluctuate?
Note:
Appliance may enter lockout during this test, reset as required until test complete.
Approximately 10 seconds after DHW demand, measure for AC voltage
between connection C1 on the PCB and a suitable Earth.
Voltage measured will be seen to fluctuate on the multimeter.
The image above is only an example of what a multimeter fluctuating looks like, your multimeter may display different readings.
Does the voltage fluctuate?
Note:
Appliance may enter lockout during this test, reset as required until test complete.
Isolate as per TOPs P4
and refit as necessary