Air Conditioner Anatomy: How Your System Keeps You Cool All Summer Long

Air Conditioner Anatomy: How Your System Keeps You Cool All Summer Long

An air conditioner can keep your house cool even on the hottest Illinois summer day. But how does it do so? To understand this miracle of modern technology, you have to take a look at air conditioner anatomy.

An A/C system is made up of multiple different parts that work together to take heat from inside the home and deposit it outside. The basic parts of air conditioner anatomy are:

  • Thermostat. This is basically just an on/off switch that is triggered by changes in air temperature.
  • Refrigerant. This is not a solid piece of equipment, but rather a substance that flows throughout the system. Refrigerants, such as R-22 or R-410A, absorb and release heat as they change from liquid to gas and back again.
  • Compressor. Located in the outdoor A/C unit, the compressor pressurizes the refrigerant. Under very high pressure, it doesn’t have room to be a gas; it has to condense into a liquid.
  • Condensing coil. The refrigerant condenses into a liquid in the outdoor condensing coil. It has to release heat to condense, and the radiator-like coil (and accompanying fan) allows that heat to dissipate into the outdoor air.
  • Expansion valve. The liquid refrigerant flows into the house. An expansion valve in the indoor A/C unit gives the liquid room to expand, so it can evaporate back into a gas.
  • Evaporator coil. The indoor version of the condensing coil allows the refrigerant to absorb heat from the air. It has to absorb heat to boil (remember, it has a sub-zero boiling point, and even cool air contains some heat). The indoor blower fan pushes the necessary air across the coil, and the chilled air then flows throughout the house.

The refrigerant then travels back outside to the compressor, and the cycle continues.

Heat pumps have the same basic air conditioner anatomy, since they are also used for cooling. The difference is that they can run in reverse, bringing heat into the house for heating.

If you have any questions about air conditioner anatomy, or if any of your A/C parts need repaired or replaced, please contact us at Ernst Heating & Cooling. We provide superior HVAC services to Edwardsville, Glen Carbon, Maryville, Hamel and other Metro East Illinois communities.

Image courtesy of Shutterstock

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