Low
F6 on Ideal INDEPENDENT SYSTEM

Your boiler is having trouble reading the outdoor temperature, which it uses to help run your heating more efficiently.

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

Outside Sensor Fault

Shared across the INDEPENDENT System 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 the external sensor on the outside of your house for any obvious damage or loose wiresTurn the boiler power off and back on to see if the fault clearsEnsure there is no debris or ice covering the outdoor sensor

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All 20 fault codes on the INDEPENDENT SYSTEM

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

F1F2F3F4F5F7F8F9FnFUL1L2L4L5L6L8L9LCLn

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