Emergency
Er09 on Biasi Concept 400 20 1 Mfs

Your boiler has detected an issue with its exhaust system or the sensor that monitors exhaust heat, causing it to shut down for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Flue pipes / Flue temp. probe NTC - check Flue pipes, Flue temp. probe NTC

From this model's manual
Verified against the Biasi Bm Biasi Concept 400 20 1 Mfs installation & service manual, page 10.
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 is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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