wunder beta❄️ How Air Conditioners Work
The hot air leaving the outdoor unit used to be in your living room. Follow the refrigerant loop that carries it.
What you’ll learn
- The heat-moving ideaExplain how a vapor-compression air conditioner moves heat from indoor air to outdoor air instead of making cold.Electricity drives a sealed refrigerant loop so heat leaves the room at the evaporator and is dumped outdoors at the condenser.
- The two sides of the circuitShow why pressure changes are what make heat willing to leave a room that is already cooler than the street.Compression makes the outdoor coil hotter than outdoor air; expansion makes the indoor coil colder than room air.
- The room sideDescribe how the indoor coil and fans cool circulating air and, when the coil is below dew point, dry it.Airflow across a cold evaporator transfers heat and can condense moisture; the drip is humidity leaving the air.
- Control and performanceRelate thermostats, filters, efficiency ratings, and refrigerant rules to the system you actually live with.Controls request cooling, filters protect airflow, ratings are laboratory tests, and refrigerant handling is certified work.
Questions this course answers
What is an air conditioner mainly doing during cooling?
The refrigeration cycle absorbs heat indoors and rejects it outdoors while using electrical energy to drive the process.
Put the main refrigerant stages in order.
Compression, outdoor heat rejection, expansion, and indoor heat absorption form the repeating vapor-compression sequence.
Match each air-conditioner part to its main job.
The four major refrigerant-side components divide the cycle into compression, condensation, expansion, and evaporation.
Why can a dirty filter reduce cooling performance?
A loaded filter increases air resistance and can reduce the airflow the blower sends across the evaporator.
Explain why an air conditioner can make a room drier while it cools it.
The indoor coil removes both heat and, when it is colder than the air's dew point, moisture from the air.
Grounded in trusted sources
- U.S. Department of Energy, Energy Saver 101: Home Cooling: https://www.energy.gov/sites/prod/files/HomeCooling101-final.pdf
- U.S. Department of Energy, Purchasing Energy-Efficient Residential Central Air Conditioners: https://www.energy.gov/cmei/femp/purchasing-energy-efficient-residential-central-air-conditioners
- Dorothy Gerring, Renewable Energy Systems for Building Designers, Chapter 11 (DOE Building Technologies Office / PNNL): https://bsesc.energy.gov/sites/default/files/2023-09/Renewable%20Energy%20Systems%20-%20Chapter%2011.pdf
- U.S. Environmental Protection Agency, Homeowners and Consumers: Frequently Asked Questions (HCFC-22): https://www.epa.gov/ods-phaseout/homeowners-and-consumers-frequently-asked-questions
- U.S. Environmental Protection Agency, Section 608 Technician Certification Requirements: https://www.epa.gov/section608/section-608-technician-certification-requirements
- U.S. Environmental Protection Agency, Technology Transitions HFC Restrictions by Sector: https://www.epa.gov/hfcs/technology-transitions-hfc-restrictions-sector
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