Single Room Air Conditioners – A Buying Guide
Once you have the right information, choosing the right single room air conditioner is an easy process. Learn more in this Consumer Reports video buying guide.
Learning the terminology is an important step before you go shopping.
Packaged Terminal Heat Pump/Air Conditioner: Found in motel/hotel rooms, these are large heating and/or cooling units that are installed through the wall.
Chassis: A slide-out chassis slides out easily for replacement or maintenance and is found on units that are installed through the well. A fixed chassis is found on smaller, lighter weight units, making them easier to remove for winterization.
Fan: When combined with an adjustable thermostat, a variable-speed fan is an effective cooling machine. You’ll want adjustable louvers that move right/left and up/down.
Filter: For your room air conditioner to work efficiently, clean air is essential. Units should have filters that can be replaced or easily cleaned.
Thermostat: A heat-sensing device, thermostats adjust the temperature of the air coming from the unit and can be manual or programmable. You can find AC units with digital temperature readouts, 24-hour delay timers and remote control features.
BTU: An international energy measurement, the BTU (British Thermal Units) is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. A BTU measures how much heat an AC unit can remove from a room. Single room air conditioners run from about 5,000 to 24,000 BTUs. The room will not cool efficiently if the BTU rating is too high or too low for the room size, so matching the size of the room to the BTU requirements is important. The weight, size and cost of the air conditioner increases as the BTU rating increases.
EER: The EER or Energy Efficiency Ratio is an indicator of how efficient the AC unit is and is calculated by dividing BTUs by the number of watts. Ratings range from 8 to 11.5. Higher EER rated air conditioners are more efficient, but they are also more expensive. A rating of 10 or higher is recommended for hot climates.
Assessing the Room
The number of windows, ceiling height and number of people in the room are some of the factors to consider when buying a single room air conditioner. A large unit is not necessarily better; if it’s too large, it will cycle on and off repeatedly, wasting energy and causing the electrical components to wear out unnecessarily.
Calculate the square footage of the room by multiplying the width by the length and measure the inside dimensions of the window. Take these measurements along when you go shopping.
You also need to check the room’s power supply to ensure the circuit can handle the AC unit operation. Smaller units will work with the standard 115-volt outlet, while very large units require a 230/208-volt circuit. You should never alter the plug to fit the outlet. If you need to add a new circuit, you should have a licensed electrician connect the power to the panel box. The air conditioner should always be properly grounded.
Based on Energy Star guidelines, a 100-150 sq. ft. room will require a single room air conditioner with a 5,000 BTU/hr capacity, a 300-350 sq. ft. room will require a 8,000 BTU/hr capacity, a 450-500 sq. ft. room will require a 12,000 BTU/hr capacity and a 700-1000 sq. ft. room will require an 18,000 BTU/hr capacity.
