Air conditioning (often referred to as AC,A/C,or air con) is a system used to cool down the temperature in an inside space by removing the existing heat and moisture from the room. In simple terms, an air conditioning system controls the temperature, humidity, and air quality in indoor spaces. There are six different types of air conditioners that are each designed for a different space/reason. These aix types AC units are the basic central AC, ductless, window unit, portable unit, hybrid, and geothermal. There are so many problems with air conditioners like 1. The air conditioner is not turning on, 2. Air conditioner not blowing cold air.