Low
Er08 on Biasi ActivA 18S

Your boiler is having trouble communicating with an outdoor sensor used to monitor the weather, but it should still be able to provide heating and hot water.

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 temperature probe NTC (if fitted)

From this model's manual
Verified against the Biasi Activa 18s installation & service manual, page 12.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check if an external temperature sensor is actually installed on an outside wall.Inspect the sensor for any obvious physical damage or loose wiring.Restart the boiler by turning the selector knob to the 'Reset' position for five seconds.

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