BoilerFaultCodesYour boiler has switched itself off because it has detected that it is getting far too hot inside.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Safety limiter has tripped.
What causes this fault?
This fault occurs when the water temperature inside your boiler exceeds a safe limit, causing the safety sensor to shut the system down to prevent damage. The most common reasons are a failed internal pump that isn't moving water away quickly enough or a buildup of sludge and limescale that is restricting flow through the heat exchanger.
This fault is more common in the autumn when heating systems are switched back on after a long summer break, as internal pumps can seize up due to inactivity.
DIY fix possible
Check that the boiler pressure is between 1 and 1.5 bar on the needle gauge.Ensure all radiator valves are fully open to allow water to flow.Press the 'Reset' button on the front of the boiler once the system has cooled down.
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 Greenstar 30HE 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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