High
30 (ll) on Ariston Clas HE 28

Your boiler's internal computer is having trouble talking to its main control board, which has caused it to shut down to prevent incorrect operation.

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 defect with the main 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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