Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to AC Volts 
Boiler mains switch ON
CH Demand
CH Demand
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Allow the ignition sequence to commence and burner to ignite.
Measure the voltage across the red and purple leads at the diverter valve connector at the PCB.
Measure the voltage across the red and purple leads at the diverter valve connector at the PCB.
Isolate as per TOPs P4
and refit as necessary