Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Attach U-gauge to gas valve outlet pressure test point
Hinge down front facia panel and set boiler to MIN output setting
using the gas valve mode switch
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Measurement:

Allow boiler to commence its ignition sequence and ignite.
Is the MIN burner pressure 3.8mbar ?
Set boiler to MAX output setting via the gas valve mode switch.
Is the MAX burner pressure 35.5mbar?
Notes:
1. When U-gauge is removed pressure test point should be tightened & checked for gas tightness.
2. If both pressures are ok, set the boiler back to normal mode via the gas valve mode switch