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

From this model's manual
Verified against the Ideal Instinct2 24 installation & service manual, page 80.
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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