Set Appliance State:

Mains Power Off
CH Demand
CH temperature control to maximum
DHW temperature control to minimum
Loosen the outlet test point screw (P2) and attach U-gauge to the test point.
WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure
Mains Power On

Measurement:

Allow boiler to fire.
Does the burner pressure increase to its set pressure after
approximately 90 seconds?
Does the CH system begin heating correctly?
Note: If the CH burner pressure has been set at its minimum
rate, then the burner pressure will not increase.
When the U-gauge is removed, ensure the pressure test point is
checked for soundness.