BoilerFaultCodesYour boiler has too much water inside it, causing the internal pressure to rise to an unsafe level.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Upper water pressure (>2.7b)
What causes this fault?
This fault occurs when the water pressure inside your heating system exceeds a safe operating limit, often because the filling loop valve has been left slightly open or is leaking water into the system. It can also happen if the expansion vessel, which manages pressure changes as water heats up, has failed or lost its air charge. In some cases, a faulty plate heat exchanger may be allowing high-pressure mains water to leak internally into the heating circuit.
This fault is more common in autumn when homeowners top up their boiler pressure for the first time before winter and accidentally overfill the system.
DIY fix possible
Locate a radiator bleed valve and use a radiator key to release water into a cloth or bucket.Monitor the pressure gauge on the boiler until it drops back down to between 1.0 and 1.5 bar.Ensure the filling loop valves under the boiler are tightly closed to prevent more water from entering the system.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 2.7bar — no call-out fees, no surprises.
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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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