BoilerFaultCodesYour boiler has detected that there is too much water in the system combined with high temperatures, causing it to shut down for safety.
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 with temperatures reaching
What causes this fault?
This fault occurs when the internal water pressure becomes too high while the boiler is running, often caused by a faulty filling valve that is letting too much 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. When these two factors combine, the boiler shuts down to prevent internal components from being damaged by the excessive force.
This fault is more common during the first cold spell of autumn when the heating is turned on for the first time in months, putting sudden stress on the expansion vessel.
DIY fix possible
Locate your radiator bleed valve and use a key to release water into a cloth or bowl.Monitor the pressure gauge on the boiler until it drops back into the green zone (usually 1.0 to 1.5 bar).Ensure the external filling loop valves 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 E44 — no call-out fees, no surprises.
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Worcester Bosch WR325 RSF 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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