High
ON ON ON on Baxi Suprima 40

Your boiler's internal electrical system is experiencing a communication fault, meaning the control board cannot talk to the key components 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

Low voltage wiring harness error

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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