Medium
4.11 on Ideal Atlantic Combi

Your boiler is currently unable to provide heating to your radiators, although your hot water taps will continue to work as normal.

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

NO CH OPERATION BUT DHW WORKS OK

From this model's manual
This code was read directly from the manufacturer service manual for this model.
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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Related fault codes

4.10View →4.12View →

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