Parts of an Air Conditioning System

Action Heating & Cooling Inc. repairs air conditioning systems and all of the major components like A/C compressors, condensers, air handlers, and more. We serve Lakeland FL and Polk County, including Auburndale FL, Winter Haven FL, Mulberry FL, Bartow FL and more.

ac service lakelandUnlike the basic operation of a furnace, air conditioning units are a bit complicated and harder to understand. Your A/C unit is really a complex system constructed with a number of different components that all work together to remove heat & humidity from your indoor living space and transfer it outside.

When every part in your air conditioning system is operating as it should, the result is maximum efficiency, lower utility bills, and a longer useful life. When one component breaks down, the entire system can stop working. Here’s a look at the major components of an air conditioning system.


The compressor is the heart of your A/C unit. It is also often the most misdiagnosed part in the whole system. The compressor is what pumps the refrigerant through the system in a big loop. Its function is to circulate the refrigerant under pressure by changing low pressure gas into high pressure gas in order to concentrate the heat it contains. The compressor forces this high pressure gas into the condenser unit.


The condenser, or condensing unit, is the outdoor part of the air conditioning system. The condenser unit contains a condensing coil; inside of which high temperature, high pressure refrigerant gas (Freon) flows. The condenser also contains a fan which blows air over the condensing coil in order to cool the gas inside the coil back into a liquid state. Essentially, this component functions as a heat transfer point for collecting heat from, or dispelling heat to, outdoor air.

Air Handler & Evaporator Coil

Once the high pressure refrigerant gas moves through the expansion valve of the condenser and becomes cool low pressure liquid, it moves on to the evaporator coil. The evaporator coil is in the air handler portion of your air conditioning system, located in the home and functions as the heat transfer point for cooling indoor air. This area is where the hot air from your indoor living space blows across the evaporator coil by the air handler fan and cools off before blowing back into your home via the duct system.

Duct System

The duct system is the serious of vents and passages that distribute the conditioned air back into your living space and collect hot air and transfer it to the air handler where it will be cooled again.