High Lockout
L5 on Ideal Logic+

Your boiler has been manually reset too many times in a short window of time as it tries to clear a persistent underlying fault.

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

5 boiler resets in 15 minutes

What causes this fault?

This fault occurs when the boiler is manually reset five times within a fifteen-minute window, causing the system to lock you out for safety. It is usually triggered because you are trying to clear a different, persistent error that hasn't been fixed, such as an ignition or flame failure. The boiler essentially stops responding to prevent potential damage from repeated failed start-up attempts.

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

L2View →F2View →L1View →

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