High Information
S.13 on Glow-worm Ultracom 2 SXI

Your boiler is struggling to light the gas flame and is currently stuck in the ignition phase.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

ignition

What causes this fault?

This fault occurs when the boiler's internal computer tries to start the combustion process but cannot confirm that a flame has successfully lit. This is usually caused by a buildup of carbon on the ignition probes or a mechanical failure in the gas valve that prevents fuel from reaching the burner. Without a sustained flame being detected, the system stays in this phase to prevent unburnt gas from building up.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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