High
13 on Ariston Euro Combi 30 MFFI

Your boiler has detected an internal communication error or a logic failure within the main control system, meaning it cannot verify if it is running safely.

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

Check of the general performance of the unit.

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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