Low
F39 on Ferroli Bluehelix Tech RRT 24C

Your boiler has lost connection to the weather sensor outside and is defaulting to a standard internal setting to keep your home warm.

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

(Optional) External probe fault

From this model's manual
Verified against the Ferroli Bluehelix Tech Rrt 24c installation & service manual, page 44.
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

F37View →F40View →

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