Medium
F39 on ECA Confeo Premix HCH

Your boiler has lost connection with its outdoor thermometer, which helps it decide how hard to work based on the weather.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

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 your boiler control panelPress and hold the Reset button for 3 to 5 secondsWait for the boiler to restart; if the code returns, contact a professional to check the sensor wiring

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