BoilerFaultCodesYour boiler is not receiving enough gas to operate correctly, which is preventing it from staying lit.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Gas flow rate set too low. Gas pressure and connections.
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the supply of gas is insufficient to maintain a safe and stable flame. It is usually caused by a physical blockage in the gas pipework, a failing component that controls the fuel flow, or an issue with the external gas meter regulator. The boiler stops running as a safety precaution because it cannot achieve the correct heat output to operate reliably.
This issue often surfaces during the first cold snap of winter when high demand for heating puts the maximum strain on the gas supply and reveals underlying pressure issues.
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 6d — no call-out fees, no surprises.
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