BoilerFaultCodesYour boiler has detected that hot water is flowing in the wrong direction or is blocked, which usually means the system lacks enough water or has trapped air preventing a proper flow.
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 is higher than the flow temperature. Insufficient water. No through flow. Too much air in the system. Sensors not wired correctly. Deviation in the flow or return temperature sensor.
DIY fix possible
Check your boiler pressure gauge; if it is below 1 bar, top up the system using the filling loopBleed all radiators in the house starting from the ground floor up to the top floor to release trapped airEnsure all radiator thermostatic valves are fully open to allow water to circulate freely
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A boiler cover plan would cover faults like é2 — 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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