Low
F6 on Ideal Independent System S15

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

From this model's manual
Verified against the Ideal/Ideal G101 Ideal Independent System S18 4175070 installation & service 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 23 fault codes on the Independent System S15

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

F1F2F3F4F5F7F8F9FnFUL1L2L4L5L6L8L9LCLnNO CHNO DISPLAYNO HW

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