Low
Er 08 on Biasi Advance 25C

Your boiler is struggling to communicate with the outside temperature sensor, which helps it run efficiently.

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 Advance 25c installation & service manual, page 13.
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

Turn the boiler power off and back on to see if the error clears.If the fault persists, use the boiler's control panel to turn off 'Weather Compensation' mode to bypass the sensor.Check for any visible damage to the wire leading to the small plastic box on your outside wall.

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