High Lockout
E17 on Remeha Quinta 30

Your boiler's internal computer has suffered a critical software or hardware failure and can no longer control 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

Internal control box failure: check/replace the control box.

What causes this fault?

This fault occurs when the boiler's main electronic brain suffers a hardware failure or a corruption of its internal data. It is usually caused by electrical wear over time or a power surge that damages the circuits responsible for managing the boiler's safety sequences.

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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Related fault codes

E10View →E11View →E12View →E36View →

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