BoilerFaultCodesYour boiler’s internal computer has developed a serious electronic fault and can no longer control the heating process safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Control box failure
What causes this fault?
This fault occurs when the boiler's internal computer suffers an electrical failure and can no longer process data or safety checks correctly. The most common reason is a short circuit or component degradation on the printed circuit board, often caused by age or power surges from the mains supply.
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 15 — no call-out fees, no surprises.
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Remeha Quinta 30 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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