BoilerFaultCodesYour boiler has detected that water is not circulating through the system quickly enough, causing it to overheat and shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Temperature difference flow/return too high (no or insufficient flow)
What causes this fault?
This fault occurs when the water inside the boiler heats up too quickly because it isn't being moved away into your radiators fast enough. The most common reasons are a pump that has failed or become seized, or a blockage within the main heat exchanger that is restricting water flow. It can also be caused by air trapped in the system or a build-up of sludge that prevents the heat from being transferred effectively.
This issue often comes to light during the first cold spell of autumn when the heating is turned back on after being idle all summer, which can cause the internal pump to seize.
DIY fix possible
Check that all radiator valves are fully open.Ensure your system pressure is topped up to between 1 and 1.5 bar.Listen for air in the system and bleed your radiators if necessary.Check that the isolation valves under the boiler are in the open position.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E30 — no call-out fees, no surprises.
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Remeha Selecta 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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