BoilerFaultCodesThe main computer brain of your boiler has stopped working correctly, meaning the system cannot safely control the heating process.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Control unit failure
What causes this fault?
This fault occurs when the boiler's internal computer chips or electrical circuits suffer a terminal failure, often due to age or a sudden electrical surge. The most common reason is the natural degradation of solder joints or capacitors on the circuit board, which eventually prevents the system from processing safety signals.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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 Other codes — 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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