Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to DC Volts 
CH Demand
Gain access to PCB (use Insulation Mat as required)
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Reset appliance if required
(press and hold the power button for 4 seconds then release)
When the fan starts measure for DC voltage across pin 15 on connector X20 and an earth (use the copper pipe to the gas valve as earth).
Expected voltage approximately 5.5 Vdc.
Is the voltage as expected?
(press and hold the power button for 4 seconds then release)
When the fan starts measure for DC voltage across pin 15 on connector X20 and an earth (use the copper pipe to the gas valve as earth).
Expected voltage approximately 5.5 Vdc.
Is the voltage as expected?
Isolate as per TOPs P4
and refit as necessary