Low
09 on Unical Alkon R 28 HE

Your boiler has lost connection with the sensor that monitors the temperature outside, which may cause your heating to behave unpredictably.

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 interrupted

Community-sourced, unverified
We could not tie this code to a specific manual. Treat it as indicative only.
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

08View →11View →

All 46 fault codes on the Alkon R 28 HE

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

6088910111213141516171819202122232425262728303233384344455355758081AFBLOCKdbFdHbHLHtLprbtf

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