BoilerFaultCodesYour boiler has sensed that it is getting too hot and has automatically shut down to prevent damage or safety issues.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Safety temperature limiter has responded
What causes this fault?
This fault occurs when the internal temperature of the boiler rises above a safe limit, triggering a safety switch to kill the power. The most common reasons are a failed pump stopping water flow, a blockage caused by sludge in the system, or air trapped within the heat exchanger.
This issue is more common during the first cold snap of autumn when a pump that has been idle all summer fails to restart.
DIY fix possible
Ensure all radiator valves are fully open to allow water to flow.Check if your system water pressure is too low and top it up if necessary.Wait for the boiler to cool down and press the 'Reset' button.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E9 — no call-out fees, no surprises.
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Worcester Bosch 29 HE Conventional is discontinued — time for a new one?
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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