Your boiler has been manually reset too many times in a short window of time as it tries to clear a persistent underlying fault.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: 5 boiler resets in 15 minutes
What causes this fault?
This fault occurs when the boiler is manually reset five times within a fifteen-minute window, causing the system to lock you out for safety. It is usually triggered because you are trying to clear a different, persistent error that hasn't been fixed, such as an ignition or flame failure. The boiler essentially stops responding to prevent potential damage from repeated failed start-up attempts.
DIY fix possible
Turn the power supply to the boiler off at the fused spur switchWait for 30 secondsTurn the power back on to clear the lockout memory
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A boiler cover plan would cover faults like L5 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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