Low Warning
F6 on Ideal Logic Max Plus

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.

Technical description

Outside sensor fault

What causes this fault?

This fault occurs when the boiler loses communication with the sensor installed on your outside wall. The most common cause is either a broken wire leading to the sensor or moisture entering the sensor's casing and causing a short circuit.

This fault is more common following periods of heavy rain or severe storms, which can force water into the sensor unit or damage its external wiring.

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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