High
E16 on Navien NCB 35 HE

Your boiler has detected that parts inside are getting dangerously hot and has shut itself down to prevent damage.

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

Heat exchanger overheat sensor error

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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Related fault codes

E016View →E003View →

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