BoilerFaultCodesYour boiler has started up but cannot detect the water getting any hotter, so it has shut down to prevent 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 flow temperature sensor is not detecting a rise in temperature following a burner start
What causes this fault?
This fault occurs when the boiler fires up but the internal sensors don't see the water temperature increasing as expected. The most common reason is that water isn't moving through the system quickly enough, often due to a seized pump or a blockage in the heat exchanger. Because the heat has nowhere to go, the boiler shuts down immediately to protect its internal components from overheating.
This issue often surfaces in autumn when the heating is turned back on after a long summer break, as pump components can seize up during periods of inactivity.
DIY fix possible
Check that your central heating valves under the boiler are fully openEnsure all your radiator valves (TRVs) are turned to a high settingCheck your system pressure is between 1 and 1.5 bar and top up if necessaryBleed your radiators to remove any trapped air pockets
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 260 — no call-out fees, no surprises.
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Worcester Bosch GB162 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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