What is the definition of a MUA unit HVAC? A MUA unit HVAC is a multi-zone heating, ventilation, and air conditioning system. It is specially designed to provide air conditioning and heating to multiple areas of a building or home. The MUA unit is comprised of an air handler, a condensing unit, and multiple ducted air outlets. The air handler is responsible for circulating and filtering the air, while the condensing unit is responsible for cooling and heating the air. The ducted outlets are responsible for providing conditioned air to each area of the building. The MUA unit is typically installed on the roof or in an attic space and is connected to ductwork that runs through the building. The most common type of MUA unit is the split system, which is made up of an outdoor condensing unit, an indoor air handler, and multiple ducted outlets. It is important to note that the MUA unit is not a stand-alone system