Set Appliance State:

Mains Power Off
Set Multimeter to AC Volts Set meter to measure AC Volts
Boiler Thermal Store must not be at maximum temperature.
Models with Programmer: Rocker Switch to Continuous.
Models without Programmer: Rocker switch to On.
Gas On
WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure
Mains Power On

Measurement:

Measure Mains Voltage across Connection 7 (Yellow) of the Full Sequence Ignition Box and the Main Appliance Neutral Connection.