High
E060 on Navien NCB

Your boiler has detected an issue with the air-to-gas ratio system, meaning it cannot safely control the combustion process and has shut down to protect your home.

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

Abnormal operation: Dual venturi limit switch

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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