Your boiler’s internal computer has developed a serious electronic fault and can no longer control the heating 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 processor or memory chips suffer an electronic component failure, meaning the motherboard can no longer process data or safety instructions. The most common reason is natural electrical wear and tear over time, though it can also be triggered by a sudden power surge or moisture getting into the casing.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like 10 — 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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