BoilerFaultCodesYour boiler is taking longer than usual to light, though it is still currently working.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Average ignition times
What causes this fault?
This issue occurs when the boiler's control board detects that the burner is taking a few seconds longer than normal to establish a stable flame. The most common reasons are worn-out spark electrodes that can no longer create a strong spark or a build-up of carbon deposits on the sensing probe which prevents it from 'seeing' the flame quickly.
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 D.64 — no call-out fees, no surprises.
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