Medium
1 P1 on Ariston Microsystem 15

Your boiler has detected that water is not moving around your heating system fast enough, often due to trapped air or a closed valve.

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

Insuffi cient circulation indication

From this model's manual
Verified against the Ariston E Combi One 24 installation & service manual, page 38.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check that all radiator valves throughout your home are fully openCheck your boiler display to ensure the system pressure is between 1 and 1.5 barBleed all radiators in the house to release any trapped airReset the boiler using the reset button on the control panel

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1P2View →1P3View →

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