High Lockout
LD1 on Vokera Mynute 23E

Your boiler has detected a safety fault and has locked itself out to prevent damage or unsafe operation.

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

Led alarm (red)

What causes this fault?

This fault occurs when the boiler has overheated or failed to detect a flame during the startup process. The most common reasons are a build-up of excess heat due to a circulation issue or a component failure that prevents the burner from lighting safely.

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.

Find a Gas Safe engineer
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Related fault codes

AL10View →

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