BoilerFaultCodesYour boiler has shut down because it has detected its internal temperature is too hot and is now in a safety lockout.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: 2 lights flashing slowly (Primary Overheat)
What causes this fault?
This fault occurs when the water inside the heat exchanger exceeds a safe temperature, triggering a safety sensor to cut the power. The most common reasons are a failed pump that isn't moving water away fast enough or a physical blockage in the system causing the unit to get too hot too quickly.
This fault often appears during the first cold spell of autumn when the heating is turned on after being dormant all summer, which can cause internal pump components to seize.
DIY fix possible
Check that all radiator valves are fully open to allow water to flow.Wait for the boiler to cool down naturally.Press and hold the reset button for five seconds.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like FAIL POINT G — no call-out fees, no surprises.
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Worcester Bosch 24/28CDi II RSF 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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