Do You Know How Your A/C's Refrigeration Cycle Works?

July 23, 2015

The A/C in your Des Moines home uses a process called the refrigeration cycle to keep you comfortable during warm weather. During the refrigeration cycle, heat from indoors is transferred outside using special fluid called refrigerant.

Refrigerant Refrigerant is a fluid that evaporates at a low temperature, typically between 40 and 50 degrees. Its main job is to absorb the heat inside your home and bring it outside in a process that begins at the evaporator coil.

Evaporator Coil Refrigerant enters the evaporator coil as a cool liquid at low pressure. The evaporator coil is a series of tubes covered by fins. As the air from inside your home is blown over the evaporator coil, the refrigerant absorbs heat energy, turns into a gas and continues on to the compressor. The resulting cool air is then blown into your home.

Compressor Inside the compressor, the molecules of the refrigerant are squeezed together, increasing in temperature and pressure. The compressor then pumps the hot, high-pressure refrigerant to the condenser coil.

Condenser Coil As the refrigerant enters the condenser coil, it is a high-pressure gas at 120 to 140 degrees, hotter than the outdoor air. A fan blows the cooler (by comparison) outdoor air over the condenser, allowing the air to absorb some of the heat from the refrigerant inside. As the heat is removed, the refrigerant condenses back into a liquid, still at high pressure, before it continues on to the expansion valve.

Expansion Valve In the expansion valve, pressure on the refrigerant is reduced, allowing the molecules in the liquid to spread out and cool rapidly. The liquid refrigerant, now at low pressure, returns to the evaporator coil to absorb more heat and repeat the cycle. To learn more about the refrigeration cycle and how it keeps your home cool, talk to our cooling experts at Lozier Heating and Cooling. We have served Des Moines and the surrounding areas for over 100 years. Our goal is to help educate our customers in the greater Des Moines, Iowa area about energy and home comfort issues (specific to HVAC systems). Credit/Copyright Attribution: "Christian Delbert/Shutterstock"