Medium
13 on Ariston Microsystem 15

Your boiler is having difficulty performing its standard internal check, which often indicates a temporary communication glitch or a minor sensor conflict.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Check of the general performance of the unit.

From this model's manual
Verified against the Ariston E Combi One 24 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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