Low
F6 on Ideal Instinct2 24

Your boiler is having trouble communicating with the heat sensor located on the outside of your house, which helps it decide how hard to work based on the weather.

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

Community-sourced, unverified
We could not tie this code to a specific manual. Treat it as indicative only.
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

Turn the boiler power switch off and back on again to see if the error clears.Check if the sensor on your outside wall has been knocked or damaged by garden work.Ensure there is no heavy snow or debris covering the outside sensor box.

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Related fault codes

F5View →F2View →

All 45 fault codes on the Instinct2 24

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

00CHCH 80F 4 L 4F 5 L 5F 9 L 9F HF LF[-]F1F2F2 or Fn or LnF3F4F5F7F8F8 or L8F9F9 or L9FAFnFPFP 1 0FUHH 60L[-]L1L2L4L4 or F4L5L5 or F5L6L8L9LCLnoFPHPH 60UuP

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