Low
F39 on Ferroli Arean

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.

Technical description

External probe fault (Sensor damaged or short-circuited)

Engineer required

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

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Related fault codes

F37View →

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