High
E110 on Navien NCB CE

Your boiler is struggling to breathe because it cannot effectively move air through the system, meaning it has shut down for safety.

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 motor failure or APS (Air Pressure Sensor) error related to combustion air/exhaust.

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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