High
E595 on Navien NCB

Your boiler's control panel has lost its connection to the main computer, meaning the system cannot communicate or respond to your settings.

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

Communication Error with Front Panel

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

E594View →E596View →

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