High
31 on Chaffoteaux Calydra 23 Green

Your boiler's main control system is having trouble talking to the front display panel, meaning the boiler cannot receive the instructions it needs to provide heating and hot water.

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 problem with the display PCB

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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