Low
F39 on Ferroli Arena 30A

Your boiler has lost the signal from the sensor that monitors your outdoor temperature, so it is using a default setting to keep your home warm instead.

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

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 →F38View →

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