High
E110 on Navien NCB

Your boiler's air extraction system has stopped working, meaning the unit cannot safely vent exhaust gases and will shut down to prevent a hazard.

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

Fan speed failure (approximately 0 rpm), loose assembly, or defective connection

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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