BoilerFaultCodesYour boiler has too much water inside it, causing the 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 there is too much water volume in your heating system, pushing the internal pressure beyond the manufacturer's safety limit. The most common reasons are the filling loop being left slightly open, or an internal component like the expansion vessel failing to manage the pressure as the water heats up.
This fault is more common when turning the heating on for the first time in winter, as the expansion of cold water can expose a failing expansion vessel.
DIY fix possible
Locate a radiator bleed valve and use a key to release water into a jug.Monitor the pressure gauge on the boiler until it drops back down to between 1.0 and 1.5 bar.Check that the filling loop valves under the boiler are fully closed and not leaking water into the system.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
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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