High
A10 on Ariston Micro Combi 27 MFFI

Your boiler is having trouble controlling the size of its internal flame, which means it cannot safely heat your water or home.

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

Modulator

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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Related fault codes

A11View →A12View →

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