Biasi 50 Fault Code
The Biasi 50 fault code means: your boiler is having trouble talking to your external heating controls or smart thermostat, meaning it cannot receive the correct instructions to heat your home.. It appears on 4 Biasi models in our database.
Technical description: OT communication fault.
DIY fix possible
Check that your wall thermostat or smart hub is powered on and has fresh batteries if required.Ensure any wireless receiver boxes plugged into the wall are switched on and showing a green light.Try resetting the boiler by turning the dial to 'Reset' for five seconds and then back to the on position.
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Gas Safe Register →Biasi models that show the 50 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Biasi 50 fault code information on this page is sourced and cross-checked against the official Biasi service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026