BoilerFaultCodesYour boiler is overheating because water is not moving through the system fast enough to carry the heat away.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Excessive temperature rise
What causes this fault?
This fault occurs because the water inside the boiler is getting too hot too quickly, often because something is blocking the flow or the pump has failed. The most common reasons include a buildup of internal debris like lime scale or sludge, or a mechanical failure that prevents the water from circulating around your radiators.
This fault is frequently seen in autumn when heating systems are switched back on after a long summer break, as pumps can seize up during periods of inactivity.
DIY fix possible
Check if your radiator valves are openEnsure the system water pressure is between 1 and 1.5 barGently bleed your radiators to remove trapped air
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 E25 — no call-out fees, no surprises.
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Vokera Hydra 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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