BoilerFaultCodesYour boiler has detected that the water pressure inside the system is far too high, causing it to shut down for safety.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Pressure greater than 3 bar or pump pressure increase is too high
What causes this fault?
This fault occurs when there is too much water forced into your heating system, often because the filling loop valves have been left slightly open or have developed a leak. It can also be caused by a failure in the expansion vessel, which is the internal part responsible for managing the natural pressure changes that happen when water gets hot.
This issue often surfaces when the heating is first turned on for autumn, as the heat causes the water to expand and pushes an already overfilled system past its safety limit.
DIY fix possible
Locate a radiator bleed valve and use a key to release water into a container until the pressure gauge on the boiler drops to 1.5 bar.Ensure the blue or black filling loop handles under the boiler are fully tightened in the closed position.Check if the filling loop hose is still attached and disconnect it if it is a removable type.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 117 — no call-out fees, no surprises.
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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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