What is the definition of a multi zone HVAC controller? A multi zone HVAC controller is a device that is used to regulate the heating and cooling systems in a building or other enclosed area. It allows the user to control the temperature and humidity in each zone separately. The controller is typically programmed to maintain temperatures and humidity levels within a certain range, allowing for more precise control over the comfort of the occupants. Additionally, the controller can be used to limit energy consumption by allowing users to set different schedules for different zones. This can be particularly useful in larger buildings where different areas may require different heating and cooling levels. The controller is also able to provide alerts if something is not working properly, allowing for timely maintenance or repairs. In conclusion, the multi zone HVAC controller is an important device for regulating temperature and humidity levels in an enclosed area, while also providing energy savings and alerting users when something is not working properly.