Controlling split-ductless air conditioner with remote

Buying Guide: Room Air Conditioners

Purchase the perfect air conditioner for your space with efficiency in mind.

How do you know which cooling system is right when they all promise to help keep you cool? While it may seem like any room air conditioner might do, it’s important to do your research so you can choose the right unit that will not just keep you cool, but help you save on energy costs too.


Think about size first

When it comes to room ACs, bigger is not always better. In fact, an AC that is too large for a space can be less effective, decrease home comfort and waste energy.

To determine the right size, start by measuring the area you need to cool. The square footage will determine the cooling capacity needed, which is indicated by British thermal units (BTUs/hour). As a rule of thumb, average 20 BTUs for each square foot of living space. Once you’ve determined the BTUs, you’ll need to factor in a few other considerations, like windows and ceiling height:

  • If the room receives little to no sunlight, reduce BTU capacity by 10 per cent
  • If the room receives a lot of sunlight, increase BTU capacity by 10 per cent
  • If the room is typically occupied by more than two people, increase BTU capacity by 600 BTUs per person
  • If the AC unit is being placed in a kitchen, increase BTU capacity by 4,000

If you’re still not sure, consult a certified air conditioning contractor they can help you in choosing the right sized unit for your space.

Research what's available

There are a variety of room air conditioners available on the market. Before purchasing, familiarize yourself with the different types and their available features:

Window air conditioners

Window AC units can cool rooms from 100 square feet to 650 square feet. Check the BTUs to determine if your space needs a small, medium or large AC unit to cool the room properly. Small-to-medium sized units are relatively easy to install, but larger window units may require installation by a contractor. All units can typically be installed in single or double hung windows, and most come with adjustable panels that ensure the AC is properly fitted to your window, reducing the risk of air leaks.

Portable air conditioners

These AC units can be moved from room to room, making it easy to cool specific areas when needed. Most portable units have a venting kit for the exhaust, so keep this in mind when thinking about placement. If the unit has a hose to utilize outside air, you’ll need to make sure it can be placed near a window.

Split ductless air conditioners

Split ductless air conditioners are a great way to cool multiple rooms without having to install multiple window units or the ductwork needed for central air conditioning. Upfront costs may be higher than alternatives and you'll require a contractor to install the system, but these units are typically more energy efficient and have additional features like air filtration.

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Identifying an energy-efficient model

There are two labels to look out for when identifying the energy efficiency of a model, the ENERGY STAR® label and the ENERGUIDE label.

ENERGY STAR label: this designation helps you identify systems that provide the best performance while using the least amount of energy. On average these models use ten per cent less energy than other standard models.

ENERGUIDE label: This label includes the model type and its energy efficiency ratio (EER). The higher the ratio number the more efficient it is. The label includes a EER scale to show you the range available for similar models, as well as an indicator that shows where the model falls on the scale.

Keep an eye out for other energy-efficiency features like an energy-saving setting. This feature allows the unit to operate at a low setting keeping the room comfortable while using less energy. Or look for a model with a timer which allows you to set when you want the AC to be working, letting you keep cool when you need it without having to constantly run the unit.

Ask questions, compare…and enjoy!

As you set out on your hunt for the perfect room AC, remember to ask questions. Certified air conditioning contractors can help you find what you’re looking for, and may also help you properly install a unit. The ENERGY STAR® Product Finder tool is also a great resource that allows you to compare different energy-efficient makes and models, which will make your purchasing decision easier.

Happy shopping!

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