High
AL74, AL79 on Vokera Sabre 29H

Your boiler has encountered a technical communication or internal sensor error and has stopped working as a safety precaution.

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

Reset the boiler. If the fault reoccurs, contact a heating engineer.

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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