BoilerFaultCodesYour boiler has detected that the water pressure in your radiators is falling much faster than expected, which could indicate a significant leak.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pressure drop in heating system too rapid
What causes this fault?
This fault occurs when the boiler detects a sudden and significant loss of water pressure within the central heating circuit. It is usually caused by a large leak in the pipework or a failure in internal components like the expansion vessel, which forces water out of the system. The boiler shuts down as a safety precaution to prevent the internal heat exchanger from overheating without enough water to cool it.
This fault is more common when the heating is first turned on after summer, as the change in temperature and pressure can stress weakened seals or joints, leading to new leaks.
DIY fix possible
Check all visible radiator valves and pipework for signs of water leakingTop up the system pressure to between 1 and 1.5 bar using the internal filling linkRestart the boiler to see if the code clears and the pressure remains stable
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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