Low
CO on Vokera Linea 28

Your boiler is currently set to a special testing mode used by engineers to check its performance, rather than operating in its normal heating mode.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Confirm the appliance is in combustion test mode

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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