Medium
J on Main Eco Compact Combi

Your boiler has detected trapped air or a temperature reading issue in the water system, which usually causes it to pause for safety.

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

Flow temperature sensor / air in system

Shared across the Eco Compact range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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 pressure gauge to ensure it is between 1 and 1.5 bar.If the pressure is low, use the filling loop to top it up.Bleed your radiators to remove any trapped air in the heating system.

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Related fault codes

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All 71 fault codes on the Eco Compact Combi

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

0915202840103104107109110118125128130133134135160321384BatCC13DEE01E04E05E06E10E12E13E14E15E16E17E19E20E21E22E24E27E108E110E117E118E125E127E128E130E133E160E193E220E227E260E320E321E327E384E385FGG20HIIPX5DKLM

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