Have a Residential system. One unit, dual zone forced air HVAC. 2 thermostats. Is this type of unit designed to run the heat downstairs, while running the AC upstairs at the same time? The house/unit is 2 yrs old. We have had multiple issues with the system from inside and outside fans running nonstop. AC not wanting to come on upstairs, Fan downstairs will run continuosly but doesn’t keep up to the temp of 71 that it is set for, Vice versa with the AC upstairs.