Low
F39 on Ferroli iBoiler 28

Your boiler has lost connection with its outdoor temperature sensor, which helps it run more efficiently 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.

Technical description

Optional external probe error

DIY fix possible

Check if the boiler operates normally for heating and hot water despite the codePress the Reset button on the control panel to clear the temporary errorIf the code persists, contact a professional to check the external sensor wiring

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Related fault codes

F37View →F05View →

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