BoilerFaultCodesTechnical 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
Check that the internal or external filling loop valves are tightly closedBleed water from a radiator using a bleed key to reduce system pressureMonitor the pressure gauge until it returns to the normal range (typically 1.0 to 1.5 bar)Restart the boiler if the fault code does not clear automatically
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