When the subject of HVAC comes up, a lot of other things usually pop up along with it. HVAC is short for Heating, Ventilation and Air Conditioning. Simply put it is a machine that is made to provide the services previously mentioned. In earlier times qualityaircarefl you would find machines would be made separately for heating, ventilation and air conditioning. However, with credit given to the improvement of science, its now possible to have all three technologies combined into a single machine.