BoilerFaultCodesYour boiler is failing to light the flame after multiple attempts, which is often caused by an issue with the air supply or exhaust gases leaving the building.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ignition problem at the first start – this could be due the flue line, possible flue blockage or chimney gasket.
What causes this fault?
This fault occurs when the boiler tries to light the flame several times but fails because the air coming in or the waste gases going out are restricted. This is usually caused by a blockage in the flue pipe or a perished seal that is letting exhaust gases leak back into the air intake, starving the burner of oxygen. It effectively prevents the boiler from breathing properly, so it shuts down for safety.
This issue can become more frequent during periods of high winds, which can interfere with the pressure inside the flue and highlight existing blockages or seal failures.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Could it be time for a new boiler?
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