BoilerFaultCodesYour boiler is overheating because water isn't moving through the system quickly 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 when the boiler's internal temperature rises too rapidly, triggering a safety shutdown to prevent damage. The most common reason is a blockage or restriction in the system pipes, or a faulty pump that is failing to circulate hot water away from the burner quickly enough.
This issue often surfaces during the first cold spell of autumn when heating systems are turned on after being dormant all summer, which can cause internal pump parts to seize.
DIY fix possible
Check that at least two or three radiators have their valves turned fully openEnsure the external heating pump (if visible) is runningReset the boiler once the system has cooled down
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 Pinnacle 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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