Low
F6 on Ideal Independent C24

Your boiler is struggling to detect the current outdoor temperature, which means it cannot automatically adjust your heating to match the weather outside.

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 Failure

From this model's manual
Verified against the Ideal/Ideal Independent C24 4734924 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.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F5View →

All 24 fault codes on the Independent C24

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

dUF1F2F2 or Fn or LnF3F4F4 or L4F5F5 or L5F7F9 or L9 or F8 or L8FAFNFUL1L2L4L4 or F4L5L5 or F5L6LCLN

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