Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Attach U-gauge to burner pressure test point
Disconnect blue wires from gas
valve modureg and make safe
Set service potentiometer to MIN
Gas On
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Allow burner to ignite and establish.
Is the minimum burner pressure as per the table?
Boiler OutputNatural GasLPG
24kW0.9mbar3.1mbar
28kW0.7mbar2.8mbar
             (for RD628 use 28kW values)
Note: When pressure gauge is removed the pressure test point should be tightened and checked for gas tightness.