Room air conditioner

What it is

The much more efficient options are room air conditioners with efficient variable speed compressors, which can vary the speed of the internal compressor motor to continuously control the temperature.

In a conventional room air conditioner, the compressor works like an on/off switch. It is either "on" at maximum capacity when the thermostat calls for cooling or "off" when the desired temperature has been achieved, and alternating between on and off periodically to maintain temperature.

Source: ENERGY STAR

Its parts

Compressor

Condenser

A pump that moves refrigerant between the evaporator and the condenser to chill the indoor air.

Systems that have the evaporator, condenser and compressor in one unit are called packaged systems.

Source: U.S. Department of Energy

Evaporator coil

Evaporator coil means a component of a central air conditioner that is designed to absorb heat from an enclosed space and transfer the heat to a refrigerant.

Source: Code of Federal Regulations

Air filter

Most filters are designed to filter either particles or gases.

Furnace and HVAC filters work to filter the air only when the system is operating.

Most comfort conditioning systems that circulate air incorporate some form of air filter.

Source: U.S. EPA · ASHRAE

Through-wall air conditioner

PTAC

FEMP's acquisition guidance and associated ENERGY STAR efficiency requirements for room air conditioners apply to casement-only and casement-slider window air conditioners, through-the-wall air conditioners, and reverse cycle room air conditioners.

All other air conditioners are excluded, including but not limited to packaged terminal air conditioners (PTAC), portable air conditioners, models equipped with electric resistance heating elements, and products like dehumidifiers covered by other ENERGY STAR program requirements.

Source: U.S. Department of Energy

Related pages

• Glossary: Room air conditioner

  Its entry, and the guide's pages that use it.

• Window and wall air conditioners

  Window, through-the-wall and PTAC units: sizing, power and care

Sources

1. ENERGY STAR. Room Air Conditioners.
2. U.S. Department of Energy. Energy Saver 101: Home Cooling.
3. Code of Federal Regulations. 16 CFR Part 305 Energy Labeling Rule.
4. U.S. EPA. Guide to Air Cleaners in the Home.
5. ASHRAE. ASHRAE Handbook Chapter 1: Residential Space Conditioning.
6. U.S. Department of Energy. Purchasing Energy-Efficient Room Air Conditioners.
7. U.S. Department of Energy. energy.gov: Purchasing Energy-Efficient Room Air Conditioners.