A thermostat split system air conditioning unit is an energy-efficient cooling system that consists of two main components: an indoor evaporator unit and an outdoor condenser unit. The purpose of the system is to provide a regulated temperature inside a building, as well as controlling humidity. The evaporator unit is placed indoors, where it absorbs heat from the air, and then transmits this heat to the condensing unit, which is located outdoors. From there, the air conditioner circulates cooled air into the structure. By leveraging a smart thermostat, the system can be adjusted to achieve maximum efficiency.