BoilerFaultCodesYour boiler has too much water in the system, which puts extra stress on the internal components.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical 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 under the boiler are tightly closed.Locate a radiator and use a bleed key to release water into a container until the pressure gauge on the boiler drops to 1.5 bar.Restart the boiler once the pressure is back in the green zone.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E10 — no call-out fees, no surprises.
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Ravenheat CS 80/90, WH System, WH 80/90 is discontinued — time for a new one?
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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