BoilerFaultCodesYour boiler has sensed that the water inside is getting too hot and has shut itself down to prevent damage.
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 in CH flow has triggered.
What causes this fault?
This fault occurs when the internal water temperature exceeds safe limits, forcing the boiler to shut down for safety. The most common reasons are a failed pump that isn't moving water around the system or a blockage caused by a buildup of sludge and debris in the main heat exchanger.
This issue often surfaces during the first cold snap of autumn when a pump that has been idle all summer fails to restart.
DIY fix possible
Check that your radiator valves are fully open to allow water to circulate.Ensure your boiler pressure is between 1 and 1.5 bar on the front gauge.Press the reset button to see if the fault clears after the system cools down.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E9 — no call-out fees, no surprises.
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Worcester Bosch RD 532i RD 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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