Medium
P11 on Ferroli Leb TS

Your boiler has detected trapped air bubbles moving through your heating pipes, which is preventing the system from circulating water effectively.

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

Air release in CH return pipe

From this model's manual
Verified against the Ferroli/Ferroli Leb Ts installation & service manual, page 9.
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 your boiler's pressure gauge to ensure it is between 1 and 1.5 barTop up the system pressure using the filling loop if it is below 1 barBleed all radiators in the house starting from the ground floor and moving upwards to release trapped air

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Related fault codes

P12View →F37View →

All 23 fault codes on the Leb TS

Seeing a different code? Every code this model can display, in one place.

A01A03A06A08F10F13F14F37F41FDP01P02P03P04P05P06P07P08P09P10P12P13

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