In this article:

• Types of Window & Room Air Conditioners
• Energy Efficiency of Window & Room Air Conditioners

An unbiased window and room air conditioner buying guide, including information on types and energy-efficiency.

By Don Vandervort, HomeTips

Today’s window and room air conditioners are quiet-operating marvels of design that can meet most any cooling demand, regardless of a room’s size or function. There are many energy-efficient models with a range of features, from digital thermostats to remote controls and variable fan speeds.

About one-quarter of American households have in-room air conditioners, and the numbers are increasing. The factors that are helping to drive this popularity include:

Affordability. Small models cost as little as $100. Large room air conditioners, with greater cooling capacities, can run up to $700.

Efficiency. Many units have variable digital controls instead of the simple HIGH and LOW settings of earlier models. Units with energy-saver switches provide further help in cutting down on utility costs.

Availability. Window and room air conditioners are sold at most big-box home improvement stores, as well as at large supermarket chain stores, department stores, and even pharmacies. Frigidaire, GE, Kenmore and LG are among the top-selling brands.

Easy installation. Most window air conditioners come with easy-to-use installation kits. Free-standing portable ACs need minimal setup and can be moved from room to room.

Types of Window & Room Air Conditioners

There are three main types of room air conditioners: window units, wall-mounted units, and portable models. Following is a closer look at each:

Why we like it: • Right size for mid-size rooms • Remote control • Energy Star rating

Window units are by far the most popular. Models can be installed in most single- or double-hung windows and typically come with accordion panels that make for a secure fit. Some also fit in sliding windows.

Installing a window unit is an easy DIY project. Make sure you measure the inside window dimensions before you shop. Directions and hardware should be included.

Through-the-wall units require opening a hole in an exterior wall, a job that is considerably more involved than installing a window unit. On the plus side, they don’t take up window space, and they allow for a more airtight and secure fit.

Most window models can be installed as through-the-wall units—you just add a frame to support the unit. Small units can be installed by handy DIYers. Large units may require professional installation.

Portable air conditioners, self- contained, freestanding units, are the new kids on the block. Most have casters so they can be wheeled around to the room or rooms that need to be cooled. They come with a large, flexible hose that is attached to a window for exhausting hot air, much like a clothes dryer is vented. Though they tend to cost more than window and through-the-wall units, they are practical because of their portability.

Air conditioners remove water from the air as they cool it, which means that most portable units have reservoirs that need to be periodically emptied, though some also come with optional hookups for a drainage hose. Some new models evaporate much of the moisture and exhaust it, greatly reducing the frequency of need to empty a container.

Energy Efficiency of Window & Room Air Conditioners

All new room air conditioners are required to carry an EER, or Energy Efficiency Rating, which ranges from 8 to 11.5. The ranking is important for consumers because air conditioners with higher EERs yield the most savings in monthly electric bills.

The higher EER also helps the environment by reducing greenhouse emissions. Check the yellow Energy Guide label on new room air conditioners when you’re shopping. A rating of 10 or higher will produce the most in energy savings.

One of the best ways to ensure efficiency is to buy the right size window, wall, or room air conditioner. For an explanation of how to size one of these units, along with a sizing chart, see How to Size a Window or Room Air Conditioner.

Many of the energy-efficient features in room air conditioners also offer greater convenience and comfort and include:

Variable fan speeds. More speed settings give you greater control of air flow, which also helps save money.

Digital temperature control. The ability to control temperature by degrees—instead of with simple HIGH or LOW settings as previous models had—allows for greater comfort as well as increased energy savings.

Programmable thermostat. Though it comes as a premium, you may want to pay a little more for an AC unit that lets you program desired settings for different times of the day and night.

Easy-to-access filters. Filters remove dust and other allergens from the air. Filters that slide out make cleaning them a snap. Regular maintenance will extend the service life of your air conditioner and keep it operating at full efficiency.

Sleep setting/energy-saving setting. The unit operates at a very low setting during nighttime hours, making the room more comfortable for sleeping and at the same time saving on energy costs.

Timer. Timers are a simpler and less costly alternative to programmable thermostats. Just set the time you want the AC to start or stop. Timers let you come home to a house that already is cool without continuously running the air conditioner while you’re away.