Low
F39 on Ferroli HiTech RRT 28C

Your boiler is having trouble communicating with the outdoor weather sensor, which means it cannot automatically adjust its temperature based on outside conditions.

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 Ferroli/Ferroli Bluehelix Hitech Rrt installation & service manual.
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 →F05View →

All 36 fault codes on the HiTech RRT 28C

Seeing a different code? Every code this model can display, in one place.

A06A08A09A11A14A23-A24-F51A26A44A80A88A98A99F05F09F10F11F12F13F15 - A07F19F21F34F35F37F40F47F50F50 - F53F51F53F62F64F96F99Fh

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