PRESSURE GAS INLET DROP

Set Appliance State:

Gas Off

Isolate Mains Power to appliance as per TOPs P4

CH Demand

Attach U-gauge to gas inlet pressure test point

Gas On

WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure

Mains Power On

Observation:

If required, reset boiler.
Inlet pressure should remain above 17.4mb (N.G.) or 25mb (L.P.G.) throughout the ignition sequence.

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Note.
1. The boiler will enter lockout after 3 attempts of ignition, approximately 30 seconds between each attempt, reset as required until test is complete.
2. When the test is complete the pressure test point should be tightened and checked for gas soundness.

Allow self-check to complete and ignition sequence to commence.
Observe the U-Gauge throughout the ignition cycle, during the sparking stage of the ignition sequence there should be a noticeable dip from standing to working pressure as the gas valve opens.