Basic Parts of an Air Conditioner System

AC parts diagram

Many components make up an air conditioning system, and each part of an air conditioner requires regular maintenance to ensure cool comfort and performance in your Amarillo home. 

Understanding the main parts of your air conditioner and how they work together can help you use and care for your AC system and know when to call the licensed HVAC technicians at Amarillo Air.

Main Parts of Air Conditioner

Indoor and Outdoor AC Unit Diagram

Evaporator coil

Located in the indoor AC unit, the evaporator coil plays a major role in cooling. The coil houses refrigerant, which absorbs the heat from circulating air, creating cool and dehumidified air. The blower fan sends this air through the air ducts and to the supply vents throughout your home.

Evaporator coils are susceptible to dirt and dust buildup, which can result in poor energy efficiency and damage to your system. Signs of evaporator coil problems include:

  • Corrosion
  • Refrigerant leaks
  • Warm air from vents
  • Short-cycling 


Compressors are mechanical pumps that are vital for proper AC function. This device compresses the gaseous refrigerant into a smaller pressure to raise pressure and temperature and pumps it toward other cooling components. 

The rest of the system’s cooling components can’t function without a compressor, and a damaged compressor often necessitates a replacement AC unit. The compressor requires regular servicing to minimize the chances of untimely air conditioning replacement.

Common compressor issues include:

  • Dirty evaporator coil
  • Contaminants
  • Damaged suction lines
  • Electrical problems
  • Improper refrigerant charge


The condenser is a series of coils that works with the compressor unit to dissipate heat from the refrigerant. Refrigerant travels from the compressor to the condenser, which absorbs heat through metal fins or coils, and the condenser fan blows outside over this surface to promote fast cooling and dissipate the warm air outside. In this process, the refrigerant changes from gas to liquid, allowing cooled refrigerant to travel back to the evaporator coil via a copper tube or line.

While an AC can function briefly without a working condenser unit, it results in extra strain on the rest of your system and an inevitable breakdown. Most condenser unit problems are a result of dirty or damaged condenser coils or a malfunctioning condenser fan.

Indoor Furnace or Air Handler

Believe it or not, your furnace is vital to the Air Conditioning system, the furnace unit draws in fresh air, passes across the coil, and cools it before pushing it back out. Airflow problems, excessive noise, and cooling issues can indicate a furnace or air handler problem.

Indoor Parts of Air Conditioner

The indoor air conditioner unit houses the evaporator coil and other components that help circulate air throughout your home. Some indoor home AC unit parts include:

  • Air filter: Blocks dust, dirt, pollen, and other debris from entering the AC unit
  • Refrigerant: A compound in evaporators and compressors that absorbs heat
  • Blower fan: Circulates air through ductwork and vents
  • Thermostat: Senses and communicates temperature to the AC unit to start and stop cycling
  • Ductwork: Synthetic or metal tubs that transport air to and from your AC unit and throughout your home
  • Expansion valve: Removes pressure from liquid refrigerant to lower its temperature
  • Damper: Located inside your ducts, dampers regulate airflow to manage interior temperature
  • Supply and return vents: Function as the entry and exit points for air

Outdoor Parts of Air Conditioner

The outdoor AC unit contains a condenser coil and compressor as well as these parts:

  • Condenser fan: Pulls cool outdoor air through the condenser coil
  • Refrigerant line: Two copper lines connecting the outdoor condenser to the indoor evaporator
  • Drain line/pan: Carries water from excess indoor humidity from the indoor unit to the outside

Keep Cool in Amarillo with Amarillo Air

AC systems are complex, and knowing how their parts work helps you care for their components and know when to call the pros. Our technicians at Amarillo Air handle air conditioning repairs and services for both big and small AC systems. Contact us today to schedule a service.


CONTACT Amarillo Air Conditioning, Inc.

100% Satisfaction

Our installation technicians are the best in skill, attitude and workmanship. They will care for your home and complete the job with speed and precision. They will not wear shoes on your carpets. They will clean up when they are finished and take personal responsibility for your satisfaction. They will not smoke or swear in your home and they are drug-free. If, when they have finished in your home, they have not performed in accordance with these high standards, we won't consider the job done until you are satisfied with the results.