Medium
DU on Ideal INSTINCT2

Your boiler is currently in the middle of a specific installation mode while a heating valve part is being replaced.

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

Displayed during diverter valve actuator replacement sequence

Shared across the Instinct2 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.

Engineer required

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

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All 36 fault codes on the INSTINCT2

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

F[-]F1F2F2 Or Fn Or LnF3F4F5F6F7F8F8 or L8F8/L8F9F9 or L9F9/L9FAFNFUL[-]L1L2L4L4 Or F4L5L5 Or F5L6L8L9LCLNoFSHSLUFuP

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