Medium
E783 on Navien NCB CE

Your boiler is having trouble communicating with your wall-mounted thermostat or remote control panel, meaning it may not know when to turn on or off.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

OT-remote controller error

Engineer required

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

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Related fault codes

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