High
Burner lock out indicator on Vaillant Turbomax VU 182

Your boiler has stopped trying to light because it cannot detect a flame or is not receiving gas, leaving you without heating 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

The burner lock out indicator will illuminate. This usually means that the gas supply is turned off or has not been 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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