BoilerFaultCodesYour boiler has failed to light, which means you will not have any heating or hot water until the issue is resolved.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler failed to ignite – problem with gas valve operation, fan failing to start, ignition control board and cables
What causes this fault?
This fault occurs when the boiler's internal computer tries to start the combustion process but cannot detect a flame. The most common reasons are a lack of gas reaching the burner, a faulty fan not clearing the flue, or a failing ignition component that cannot generate the spark needed to light the gas.
This issue can occur after a period of inactivity in the summer or during cold snaps if external gas regulator components become sluggish.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 01 — no call-out fees, no surprises.
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Ravenheat CSI 120 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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