BoilerFaultCodesYour boiler has detected a safety-related issue with its internal components or airflow and has locked itself down to prevent damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Final fault, e.g.: water pressure switch, condense pressure switch, fan/flue problem, limit thermostat
What causes this fault?
This fault occurs when the boiler's safety sensors detect that the system cannot safely move air or water through the unit. It is most commonly caused by a mechanical failure in the fan or a blockage in the flue and condensate drainage system that prevents the boiler from 'breathing' correctly. In some cases, it can also be triggered if the unit overheats due to a lack of water circulation.
This fault is more frequent during periods of extreme cold, as the external condensate drainage pipe can freeze and cause a backup into the boiler.
DIY fix possible
Check that the system water pressure is between 1 and 1.5 bar on the pressure gaugeTurn the mode selector switch to 'OFF/RESET' for a few seconds, then back to the heater or hot water iconEnsure the external flue terminal is not obstructed by debris or garden growth
Find a Gas Safe engineer
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A boiler cover plan would cover faults like RED LED ON every 0.5-secs — no call-out fees, no surprises.
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Vokera Compact HE 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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