Low
SL on Ideal INSTINCT2

This is an informational status code that appears on your boiler's screen after a heating engineer has finished repairing or replacing a valve part inside.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Displayed after viewing the last 3 faults during diverter valve actuator replacement

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.

DUF[-]F1F2F2 Or Fn Or LnF3F4F5F6F7F8F8 or L8F8/L8F9F9 or L9F9/L9FAFNFUL[-]L1L2L4L4 Or F4L5L5 Or F5L6L8L9LCLNoFSHUFuP

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