How does an air conditioner work?

How an air conditioner works is actually fairly simple. The process mainly involves moving refrigerant—a chemical coolant—from the condenser (the outdoor unit) to the evaporator (the indoor unit) and back again. We’re going to walk through one cycle, starting in the condenser:

  1. The compressor condenses the refrigerant into a very cold liquid. The heat that has been removed from the refrigerant is blown out of your condenser with a fan.
  2. The refrigerant travels through tubing until it reaches your evaporator. When the refrigerant is in your evaporator, it is extremely cold.
  3. Air from your return duct—which is drawn in from the rooms in your home—is pushed upward through your filter and air handling unit by your blower so it can pass over the refrigerant-filled evaporator coils.
  4. As the air passes over the evaporator coils, the refrigerant absorbs the heat and changes into a gas. Since the evaporator coils are so much colder than the air, any moisture vapor in the air condenses on the coil (don’t get confused—this isn’t related to the outside condenser!). If you have proper airflow, the moisture on the coils will roll off into a drain—this is how your air conditioner provides dehumidification. It’s also the reason you need to maintain proper airflow at all times—if you don’t, that water will freeze on your evaporator coil!
  5. The air continues into the supply duct and is recirculated back into your home. Often, it takes multiple cycles of cooling before your indoor air reaches the temperature set on the thermostat.
  6. The refrigerant now returns back to the condenser to be compressed and start the cycle over again.

How an air conditioner works and cools your home isn’t overly complicated, it’s just a continuous process of heat transfer. If your air conditioner isn’t functioning properly, contact Dowd’s Mechanical, Heating & Air Conditioning today by calling 215-752-3638 to schedule air conditioning repair in Philadelphia, Bensalem, Yardley, or the surrounding areas.