BoilerFaultCodesYour boiler has shut down because there is too much water pressure in the system, which could lead to leaks if not addressed.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: System pressure too high (>2.9 bar)
What causes this fault?
This fault occurs when the water pressure inside your heating system rises above a safe operating level, triggering a safety shutdown. The most common reasons are that the filling loop was left slightly open after topping up the system, or an internal component like the expansion vessel has failed and can no longer manage the pressure changes as the water heats up.
DIY fix possible
Check that the filling loop valves (the silver flexible hose) are tightly closed.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.Reset the boiler to clear the fault code.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E117 — 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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