Medium
CO on Vokera Linea Plus AG

Your boiler has been accidentally switched into a special testing mode used by engineers to check exhaust fumes, rather than operating normally to heat your home.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Confirm the appliance is in combustion test mode.

DIY fix possible

Locate the mode selector or reset button on the front control panel.Turn the boiler off at the power supply for at least 30 seconds.Switch the power back on to see if the boiler resumes its standard heating mode.

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