BoilerFaultCodesYour boiler has shut itself down as a safety precaution because it has detected an internal fault or overheating.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The safety devices have been activated (lockout)
What causes this fault?
This fault occurs when the boiler's internal temperature exceeds safe limits, triggering a shutdown to protect the unit from damage. The most common reasons are a lack of water flow due to a failing pump, a blockage in the heat exchanger, or a faulty sensor sending incorrect temperature readings to the control board.
This issue is more frequent during the first cold snap of winter when a pump that has been idle all summer suddenly seizes or struggles to circulate water through the system.
DIY fix possible
Locate the reset button or selector switch on the control panelTurn the selector to the 'OFF/RESET' position and wait for 10 secondsTurn the selector back to the 'ON' position and check if the boiler fires up
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E26 — 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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