BoilerFaultCodesYour boiler is struggling to light or keep a flame going when you try to use your hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner ignition and flame detection (DHW)
What causes this fault?
This fault occurs when the boiler fails to detect a stable flame after several attempts to light while you are trying to use your hot water. The most common reasons are worn-out ignition components that can no longer create a spark or a faulty sensor that cannot verify the flame is safe to stay on.
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 4 — no call-out fees, no surprises.
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Ideal Response SE 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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