BoilerFaultCodesYour boiler has switched off because there is too much water pressure in the system, which can put unnecessary strain on the internal seals.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Water pressure too high
What causes this fault?
This fault occurs when the water pressure inside your heating system exceeds safe operating limits. The most common reason is that the filling loop valve has been left slightly open or is leaking, allowing too much water to enter the system from the mains. Over time, this extra water pushes the pressure high enough that the boiler shuts down to protect its internal components.
DIY fix possible
Check that the filling loop (the flexible silver hose) is tightly closed at both ends.Locate a radiator and use a bleed key to release water into a jug/towel until the pressure gauge on the boiler drops to 1.5 bar.Restart the boiler once the pressure has stabilized.
Find a Gas Safe engineer
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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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