Low
F39 on ECA Confeo Premix HST

Your boiler is having trouble communicating with the sensors that monitor the temperature outside, which can prevent it from heating your home 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.

What the manual says

Manufacturer manual

Outdoor Temperature Sensor Fault (blocking) — outdoor temperature sensor may be defective; press Reset; if persists notify ECA authorised service

From this model's manual
Verified against the Eca Confeo Premix Hm installation & service manual, page 42.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Locate the Reset button on the boiler control panel.Press and hold the Reset button for 3 to 5 seconds.Wait to see if the error code clears and the boiler restarts normally.

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