High Lockout
10 on Remeha Quinta 30

Your boiler’s internal computer has developed a serious electronic fault and can no longer control the heating safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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