BoilerFaultCodesYour boiler has detected that the water coming back from your radiators is too hot, which usually means the water isn't flowing through your heating system properly.
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
What causes this fault?
This fault occurs when the water returning to the boiler is nearly as hot as the water leaving it, which prevents the heat from being transferred to your rooms. The most common reason is a blockage or a pump failure that stops water from circulating through your radiators, causing heat to build up inside the boiler unit itself.
This issue often appears when the heating is first turned on after summer, as internal pump parts can seize up during long periods of inactivity.
DIY fix possible
Ensure all radiator valves (TRVs) are turned to their highest setting.Check that at least one radiator (usually the one in the hall) is fully open and not turned off.Check that the internal bypass valve or any external valves are in the open position.
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A boiler cover plan would cover faults like E13 — no call-out fees, no surprises.
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Remeha Avanta 18V 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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