Your boiler has been manually reset too many times and has temporarily locked itself to prevent further issues.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Forced reset unit unlocked
What causes this fault?
This fault occurs when the reset button has been pressed more than five times within a one-hour period. It is a safety feature designed to prevent you from repeatedly trying to start a boiler that has a persistent internal problem. The boiler essentially stops responding to resets to protect its components from further damage.
DIY fix possible
Switch the boiler electrical supply off at the spur switchWait for at least 30 secondsSwitch the power back on to allow the system to clear the lockout
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A boiler cover plan would cover faults like 153 — 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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