High
lock out on Vaillant Turbomax VUW 242/1

Your boiler has stopped working because it cannot detect a flame, most likely because the gas supply is interrupted or there is air trapped in the pipes.

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

The 'lock out' indicator will illuminate. This usually means that the gas supply is turned off, or is not purged of air.

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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