BoilerFaultCodesYour boiler has too much water in the system, which puts extra stress on the internal parts and may cause 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: Water pressure too high
What causes this fault?
This fault occurs when the water pressure inside your system has risen above the safe operating limit. The most common reason is that the filling loop valve used to top up the boiler has been left slightly open or is leaking water into the system. It can also be caused by a failure in the expansion vessel, which is meant to handle the natural pressure increases that happen when water is heated.
DIY fix possible
Locate a radiator bleed valve and use a key to slowly release water into a container.Monitor the boiler pressure gauge until the needle returns to the normal 'green' zone (usually 1.0 to 1.5 bar).Ensure the internal filling loop or external filling valves are fully closed and tight.
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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