High Lockout
17 on Remeha Quinta 30

Your boiler's main internal computer has developed a serious fault and is no longer able to manage the heating process 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 central control board suffers a hardware failure and can no longer process data or send signals to other components. The most common reasons for this are electrical surges, moisture ingress, or simply the natural degradation of the solder joints and capacitors over time as the unit ages.

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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