BoilerFaultCodesYour boiler is struggling to light its flame on the first try, which could cause it to lock out if it fails repeatedly.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Unsuccessful ignitions in the first attempt
What causes this fault?
This fault occurs when the boiler's internal computer detects that the gas didn't ignite correctly during its first starting sequence. It is often caused by a build-up of carbon on the spark electrodes or a supply issue that prevents the correct amount of gas from reaching the burner. While the boiler may try again and eventually fire up, it indicates that the ignition system is becoming unreliable.
This fault can be more frequent during the first cold snap of autumn, as electrodes and gas valves that have sat idle over summer may struggle to perform under the increased demand.
DIY fix possible
Check that your gas pre-payment meter (if applicable) has enough credit.Check that other gas appliances, like a hob, are working correctly to ensure there is a gas supply.Try restarting the boiler by pressing the reset button (usually marked with a flame or 'X').
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 D.68 — no call-out fees, no surprises.
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