BoilerFaultCodesYour boiler has sensed that the water returning to it is too hot, which suggests that the heat is not being effectively pumped away through your radiators.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Return temperature too high flow sensor temperature).
What causes this fault?
This fault occurs when the water coming back into the boiler is nearly as hot as the water going out, which prevents the heat exchanger from cooling down. The most common reason is a blockage in the system or a failing pump that isn't pushing the water through your radiators quickly enough. It can also be caused by a build-up of sludge or debris trapped in the boiler's internal filter.
This issue often surfaces during the first cold spell of autumn when the heating is turned back on after months of inactivity, which can cause the pump to seize.
DIY fix possible
Check that all radiator valves are fully openEnsure the central heating bypass valve is not closedTurn the boiler off and on again to see if the pump restarts
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A boiler cover plan would cover faults like AL26 — no call-out fees, no surprises.
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Vokera Mynute 10E 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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