BoilerFaultCodesYour boiler has shut down because it grew too hot too quickly, usually because the water inside isn't circulating properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler Max temperature exceeded for gradient (or overtemperature) Probable pump jammed or air in the circuit or Safety thermostat sensor tripped
What causes this fault?
This fault happens when the water inside the boiler gets too hot too quickly, triggering a safety shut-off to prevent damage. It is usually caused by a blockage or a pump failure that stops the water from moving through the system and carrying the heat away. Common culprits include a seized pump, a buildup of air in the pipes, or a physical blockage like limescale or sludge.
This fault is frequently seen in autumn when the heating is turned on for the first time after summer, as the internal pump can become seized during long periods of inactivity.
DIY fix possible
Wait for the boiler to cool down completelyCheck that all radiator valves and the boiler isolation valves are fully openPress the Reset button for five secondsGently bleed your radiators to remove any trapped air pockets
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A boiler cover plan would cover faults like E110 — 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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