BoilerFaultCodesYour boiler is repeatedly trying and failing to complete its ignition process, essentially getting stuck in a loop during startup.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler indicates start-up sequence (Start sequence not completed if it restarts at P1)
What causes this fault?
This fault occurs when the boiler begins its ignition sequence but fails to establish or maintain a stable flame within the required time. The most common reasons are worn-out spark electrodes that can no longer create a spark or a faulty gas valve that isn't delivering enough fuel for the fire to light. Because the system cannot confirm the presence of a safe flame, it constantly resets to protect itself.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like P1 — 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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