Set Appliance State:
Mains Power Off
Set Multimeter to DC Volts 
Turn Hot Water Tap On
Adjust DHW flow rate to approx 6 litres/min
Set hot water temperature control to number 3 position
Set hot water temperature control to number 3 position
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Allow boiler ignite and establish.
Measure for DC voltage across the gas valve modulation coil.
After approximately 45 seconds does the DC voltage vary between 4 - 10 Vdc ?
Note.
Voltage measured could be either negative or positive.
Measure for DC voltage across the gas valve modulation coil.
After approximately 45 seconds does the DC voltage vary between 4 - 10 Vdc ?
Note.
Voltage measured could be either negative or positive.
