Low
F39 on Euroterm E27 Plus

Your boiler is struggling to understand the temperature outside because a sensor has stopped working, which may prevent your heating from reaching the right temperature.

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

External probe fault

From this model's manual
Verified against the Euroterm E27 Plus installation & service manual, page 26.
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 →F38View →

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