High Lockout
41 on Remeha Quinta 30

Your boiler's computer brain has malfunctioned and can no longer control the heating system 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 internal circuit board, which acts as the boiler's brain, suffers a critical electronic failure or loses its memory. The most common reasons are age-related wear to the electrical components or a power surge that has damaged the delicate circuitry. Because the board can no longer safely monitor the gas valve or sensors, it shuts the system down to prevent an accident.

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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