High
E83/E84/E85/E86/E87 on Baxi Assure

Your boiler's internal computer has lost its connection with the main control board, meaning the parts aren't talking to each other properly.

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

No communication.

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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