High
lock out on Vaillant Turbomax VU 242

Your boiler has stopped working because it cannot light the flame required to produce heat or hot water.

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

Burner lock out. 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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