Low
08E on Biasi Concept 400 20 1 Mfs

Your boiler is struggling because it has lost the signal from the sensor that measures how cold it is outside.

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

Faulty external temp. probe

From this model's manual
Verified against the Biasi Bm Biasi Concept 400 20 1 Mfs installation & service manual, page 19.
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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