High
C 61 on Atag Q 25CR

Your boiler's electronic parts have lost their connection to each other and have stopped working entirely to keep your home safe.

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 bus communication (reset only possible by power interruption)

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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