High
E595 on Navien NCB 35 HE

Your boiler's electronic control board is having trouble talking to the display panel, meaning it cannot currently receive commands or show status updates.

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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