BoilerFaultCodesYour boiler has shut down because the water returning to the unit is too hot, meaning heat isn't being transferred properly to your radiators or taps.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Max.water temperature: Return temperature too high.
What causes this fault?
This fault occurs when the water coming back into the boiler is nearly as hot as the water going out, suggesting the heat has nowhere to go. The most common reasons are a pump failure that isn't moving the water around your house, or a blockage such as closed radiator valves or a clogged heat exchanger. It can also be caused by a faulty sensor that is incorrectly reporting the water temperature to the control board.
This issue often surfaces during the first cold spell of autumn when heating systems are turned back on after a long summer break, which can cause internal pump components to seize.
DIY fix possible
Check that all radiator valves (TRVs) are fully openEnsure the pump is running if visibleCheck that the bypass valve is not closedReset the boiler once the system has cooled down
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A boiler cover plan would cover faults like 1 9. — no call-out fees, no surprises.
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Remeha W40 60 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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