BoilerFaultCodesYour boiler has sensed that the water inside is getting too hot and has shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow temperature too high
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water is heating up too quickly or exceeding safe temperature limits. The most common reasons are a pump failure that stops water from moving through the system or a blockage in the heat exchanger that traps heat inside the unit.
This issue often surfaces during the first cold spell of autumn when the pump is required to work harder after being inactive throughout the summer.
DIY fix possible
Check that your radiator valves are open to allow water to flow.Ensure your central heating pump is running and hasn't seized.Try resetting the boiler to see if the error clears once the temperature drops.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 18 — 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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