Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Voltage 
CH Demand
Gain access to PCB (use Insulation Mat as required)
Ensure that the Boiler Thermostat is set to MAX
Ensure that the Boiler Thermostat is set to MAX
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Allow the fan to run and the pilot to ignite.
Measure the voltage across the blue and white wires at the Molex plug running between the PCB and the gas valve.
Measure the voltage across the blue and white wires at the Molex plug running between the PCB and the gas valve.
Isolate as per TOPs P4
and refit as necessary