BoilerFaultCodesTechnical description
High water pressure
What causes this fault?
This fault occurs when the water pressure inside your heating system rises above the safe operating limit. The most common reason is that the manual filling loop has been left slightly open or is leaking, allowing fresh water to constantly enter the system. It can also happen if the internal expansion vessel has failed, meaning it can no longer absorb the natural expansion of water as it heats up.
DIY fix possible
Check that the filling loop valves are fully closedBleed water from a radiator using a bleed key to reduce pressureMonitor the pressure gauge until it reaches roughly 1.5 barReset the boiler to clear the fault code
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