BoilerFaultCodesYour boiler has stopped working because it cannot get a steady supply of gas to stay 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 supply is interrupted; boiler switches over to safety mode.
What causes this fault?
This fault occurs when the boiler tries to light the flame but fails to detect one, causing the system to shut down for safety. The most common reasons are a temporary interruption in your gas supply, worn-out ignition parts that can no longer create a spark, or a faulty internal valve that isn't opening properly.
This issue is more frequent during extreme cold spells, as external gas meters or regulators can occasionally freeze or become sluggish, restricting fuel flow to the appliance.
DIY fix possible
Check if other gas appliances, like a cooker, are working to confirm your gas supply is active.If you have a prepayment meter, check that you have enough credit.Locate your gas meter and ensure the main handle is in the 'on' position.Reset the boiler by turning the main selector dial to 'Reset' for five seconds, then back to your preferred setting.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like Red flashing light (Gas) — no call-out fees, no surprises.
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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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