Air Conditioner Buying Guide

Installing an Air Conditioner into a Window

Window air conditioners are single, self-contained units that exhaust heat and humidity from the room to the outside. They have louvers on the back and sides that bring in fresh air. The air runs through coils, which are cooled by the compressor using refrigerant, and then the fan pushes the cool air back into the room.

How do I choose a window air conditioner?

The four most important things to keep in mind are window type, window size, BTUs and plug type. Window Type There are three different window types — standard windows (single and double hung) that slide up and down, slider windows that slide left and right, and casement windows that swing out. One style of air conditioner will go through a standard window, and taller, thinner models air will go through a slider or casement window. All air conditioners will come with a window installation kit with accordions to block the excess space on one or both sides of the unit. For slider and casement windows, if you have a particularly tall window you may need to purchase additional Plexiglas, wood or another filler to seal the space above the air conditioner.

Window Size You need to measure width, height, and depth. Please measure twice and order once. You have to support a window air conditioner either from the bottom with a bracket to the exterior wall, the sides with a window kit or both. If you are installing the air conditioner with a window kit, it’s important that you account for at least three to four inches for the accordians to fit into the space between the window and the air conditioner.

BTUs (British Thermal Units) BTUs are units of power — the larger the area you need to cool, the more BTUs you need. It’s important to find the right size. Buying a higher BTU air conditioner than your room size requires is not recommended. It is preferred to have the correct size air conditioner run for longer to properly remove humidity from the room — learn more. Plug Type There are two parts to plug type: voltage and amperage. Most rooms have circuits rated for a total of 15 amps of electricity, and many units have common 125V/15A plugs that can be used in most homes. If you are installing a larger unit with higher than 15 amps and more than 125 volts you may need to call an electrician to upgrade your circuitry. If you are replacing an existing unit, choose an air conditioner with same plug type to determine the right amount of amperage and voltage.

What are the pros and cons of a window air conditioner?

Window air conditioners require very little installation and you can normally install them yourself so there is low upfront cost. They are a good choice and are energy efficient if you are cooling one or two rooms and there are many to choose from.

Most window air conditioners are quiet but, since the whole system is contained in one unit they can be louder than split type air conditioners where the compressor sits outside. Window air conditioners obstruct at least part of one window and you need to either remove them or winterize them for the colder times of years.

How do I install a window air conditioner?

All window air conditioners come with a window installation kit which most people can install without professional help by sliding the unit into their window. Units with larger BTU capacity (usually 10,000 BTUs and up) are too dangerous to install in one piece because they are much heavier — these units will have a slide-out chassis. A chassis is the framework that supports the guts of the air conditioner. The chassis is designed to slide away from the back of the unit, which is called a sleeve. You remove the chassis and install the sleeve into the window. Then, you secure a bracket supporting the sleeve to the exterior wall. After the back of the unit is secure, you slide the chassis back into the sleeve.

Can a window air conditioner go through a wall?

Depending on the thickness of your wall, air conditioners with a slide-out chassis can go through a wall. You may need to install brackets to support the sleeve within the wall. You must check the thickness of your wall and the depth from the edge to the louvers of the air conditioner.

Space between the edge of the air conditioner and the louvers must be more than the thickness of your wall. Most slide-out chassis air conditioners will fit into a wall that is 8″ thick or less, you should always measure.

If your wall is too thick it can block the side louvers from venting properly which will cause your unit to burnout overtime. Then you need to look into a rear-venting through-the-wall air conditioner with a separate wall sleeve to ensure it will fit into your wall and vent properly.

Outside View	Inside View

Do some window air conditioners have heat?

Yes. There are two different type of heat. Some window air conditioners have electric heat strips and a few have heat pumps — learn more.

8 Types of Air Conditioners (Buying Guide)

Need an air conditioner? When you need one, you need one. Learn everything you need to know about air conditioners here including 8 types of air conditioners, BTU, where to buy them and more.

I’ll never forget the Summer of 2015 in Vancouver, BC. It was the summer our second son was born, which was during a heatwave like no other (for Vancouver). We had 30+ degree (Celsius) weather for at least two months, maybe three months.

Okay, I know if you’re from Florida you’re thinking, come on, that’s nothing. I agree, but most people in Vancouver don’t have air conditioners, including us. That changed that summer.

With an infant in the house, we had to get his room cool. In fact, the heatwave started before he was born, so I had gone Canadian Tire to buy one. Good thing I bought one as soon as the heatwave hit; a week later the place was sold out. Many people we know who waited to buy an air conditioner waited weeks for the stores to get new stock. There was run on them that summer.

When you need an air conditioner, you need an air conditioner. Here are your options.

Table of Contents

This is the ultimate guide to buying an air conditioner.

A. Air Conditioner Buying Guide

When looking to buy an air conditioner, there are quite a few variables to consider.

Before you buy anything, be sure to take a look at all of the different types of air conditioners available on the market.

Once you’ve decided on the air conditioning system that’s right for you, some other factors to consider include cost, BTU output, controls, and energy efficiency.

B. Types of Air Conditioners

Once you’ve decided to purchase an air conditioner, your choices will include everything from window units to central air conditioning, portable air conditioners, through-the-wall air conditioners, ductless split systems, package terminal air conditioners, swamp coolers and even geothermal cooling systems.

1. Window Air Conditioners

Window air conditioners are the most common type of air conditioning you see. As you walk down a city street in the summer and look up, you’ll see plenty of these installed in the windows above you. Or worse, but just as common, you’ll be dripped on by their condensation!

This type of air conditioner, normally mounted in a window, has an exhaust system which pushes hot air out the back and sides, while the refrigerant cooling system is pointed indoors.

Commonly, these units have the ability to cool one room at a time, and if you have a large home, you may need one of these installed in each room you want cooled. Largely inexpensive, these are still the most popular option for those who live in small homes or apartments. Another advantage of the window unit is that they can be moved between rooms as necessary and removed altogether in colder months.

One of the disadvantages of window air conditioners is losing the use of the window that it’s installed in, both in terms of access to fresh air and the amount light which enters the room. A less common concern, but one to be aware of, is that window units mounted in windows close to the ground can be easily compromised by burglars.

2. Central Air Conditioning

For those with a large home who want to cool many rooms at once, central air conditioning or “central air” as it’s commonly known, is going to be the most effective form of air conditioning.

The system begins with a cooling compressor, which is located outside of the home and is the piece that actually cools the air. A coil filled with refrigerant is used to cool the air, which is then blown by a fan and distributed throughout your house through your established ductwork.

Using these supply and return ducts, central air conditioning circulates the cool air through a building while warm air is then carried back through the return system and pushed out of the house through an exhaust system.

Your central air conditioning system will use the same system of ducts that your heating system uses to direct air from the furnace. Although most older homes will not be fitted with central air, they will have this duct system, which makes central air easy to install should you decide to do so.

Because you’re dealing with the insides of your house, this type of system requires the most planning of any discussed here. Central air requires a professional to install and will be the most expensive system we look at here.

3. Portable Air Conditioners

Similar to window air conditioners, portable air conditioners are another example of a “unitary” or self-contained air conditioning system. What this means is that like window units, portable air conditioners have all of their important components contained within one appliance.

These units are most commonly used in situations where either the design of a room or building rules and regulations prevent the installation of a window unit. The way these work is by cooling the air with a condenser coil contained inside the unit and then sending the warm air out through a large exhaust hose.

The exhaust hose is a large tube which resembles a dryer vent and connects the unit to an airtight window kit, directing the exhaust outdoors. These window kits are usually included with the unit.

As a result of the condenser and exhaust fan being located within the same casing, these units are typically a bit noisier than other air conditioners. The excessive noise is the result of the evaporator fan. This is the fan that evaporates the collected condensation inside the unit.

Also, these units have proven to be ineffective in rooms that are larger than 500 square feet.

Because of the noise and relative weakness of these units, many see the portable air conditioner as a last resort in situations where a window unit is impractical. To their credit, these units are relatively light and usually have wheels, making them easy to move between rooms.

4. Through-the-wall Air Conditioners

Just like window air conditioners, through-the-wall air conditioners bring in warm air which is then exhausted, while they send cool air back into the room. Like window units and portable air conditioners, these are self-contained or “unitary” systems.

For those without accessible windows, through-the-wall air conditioners are a viable option but require some planning because unlike window units, they will be mounted permanently and cannot be removed.

In order to mount one of these, a hole must be cut in an exterior wall, into which a sleeve is installed. These sleeves are necessary to support the weight of the air conditioner, as the wall itself is not strong enough to. As you’ll be cutting into a wall of your house, it is highly recommended that this installation is performed by a professional.

One of the advantages of a through-the-wall air conditioner versus a window unit is that you don’t lose the use of your window. Another advantage is that there is an airtight seal created, making the unit more energy efficient.

5. Ductless Split System Air Conditioners

“Split systems” are the air conditioners that provide cooling to different “zones” within a home. These systems, unlike window units or portable air conditioners, are not self-contained appliances, but as the name suggests, are comprised of a two-part system. These are most commonly used in buildings without a comprehensive duct system.

They’re called a ‘split system’ because they consist of two or more parts, the condenser unit, which is installed outdoors, and then compact blower units or evaporative units, which are usually mounted on walls, situated in appropriate areas for the ‘zones’ you want to be cool. These parts are connected via conduits, which carry the power and refrigerant lines.

The advantage to split systems is that they can cool different rooms at different temperatures, as each compact unit is equipped with its own thermostat. Because of this feature, these systems can also be even more expensive than having a central air conditioning system installed.

6. Package Terminal Air Conditioners

Package Terminal Air Conditioners or PTACs are the types of air conditioning system which is commonly found in commercial spaces such as hotels, hospitals, apartment buildings, and senior or assisted living facilities.

If you’ve stayed in a hotel before, you know that these are most often installed just above the floor and usually just below a window. The part you don’t see is that on the other side of the wall, the PTAC has an exhaust system sending warm air outside of the building.

Although they are often used in commercial settings, they are also a viable option as a home air conditioning system.

Like all air conditioners, PTACs send coolant through a compressor which cools the air, which is then re-directed into the room being cooled. Unlike central air conditioning, though, PTAC systems are ductless, which makes installation significantly less expensive than central air systems. Compared with central systems, PTACs are not too difficult to install and also cost less up front.

One of the main advantages to having a PTAC system is that in addition to being air conditioners, they often double as heating systems.

PTAC systems are generally used to heat or cool a single room. In many cases, a PTAC can be the elegant solution to a very specific problem. Imagine, for example; you’ve added a room to your house that is not connected to your central ductwork. Or if you have a room that receives an excessive amount of sunlight and gets warmer than the rest of the house. In cases like this, installing a PTAC can prevent you from overusing your central air conditioning just for the sake of cooling one room.

7. Evaporative or “Swamp” Coolers

Evaporative Coolers, sometimes referred to as “swamp coolers,” aren’t nearly as common as refrigerant air conditioners, but can be equally as effective. Unlike traditional air conditioners, which use a refrigerant, commonly referred to as Freon, swamp coolers use only air and water.

The technology behind a swamp cooler is so simple, in fact, that a version of it can be traced back to ancient Egypt.

Simply put, when air passes above or through water, the air is cooled. With this in mind, evaporative coolers pull hot air into your house through moistened pads, which cools the air. This cooled air is then distributed throughout your house.

One of the limitations of an evaporative cooler is that they can only really be used in hot, dry climates. It is the hot, dry air that causes the evaporation. In addition, swamp coolers act as humidifiers and would be undesirable in climates where humidity is already a problem.

As a result, swamp coolers are particularly popular in areas such as the American Southwest.

One of the benefits of a swamp cooler is that it uses significantly less energy than traditional air conditioners, as the only electricity being used is to operate the fan. Another benefit for the ecologically conscious is that because swamp coolers do not use Freon nor emit carbon dioxide, both of which have been proven to have detrimental effects on the environment.

8. Geothermal Heating and Cooling

Geothermal cooling is a relatively new, energy efficient technology which is rapidly becoming popular around the world.

Because of the insulating properties of the earth, the ground beneath us maintains a relatively consistent temperature of around 55 degrees Fahrenheit year-round. Regardless of what the weather is like outside, the earth 4 to 6 feet down remains relatively unaffected.

Geothermal technology takes advantage of this ground temperature to heat and cool your home more efficiently than other methods.

A piping system, often known as a “loop,” or “earth loop,” circulates water between your home, a heat pump, and the earth itself. These polyethylene pipes can be installed either vertically or horizontally, depending on the nature of the site’s geography.

In the winter, water runs through this earth loop and absorbs heat from the ground. This heat is then compressed, which raises the temperature, and then delivered into your home.

In the summer, this process is reversed. Heat from your home comes into the heat pump, the excess heat is removed and delivered into the ground, and the resulting cool air is then distributed through your home.

This system is revolutionary in that no fossil fuels are burned in order to create heat. The heat is simply being transferred to and from the earth. Electric power is being used, of course, to run the compressor, fan, and pump.

Because of the sustainability of this method, geothermal heating and cooling is becoming more popular every year, especially in Europe. in Switzerland and Sweden, over 70% of new homes use geothermal heating and cooling.

C. What to Consider Before Purchasing Your Air Conditioning System

Before you purchase an air conditioner or have an air conditioning system installed, there are a handful of factors you’ll want to consider.

1. Cost

Depending on what type of system you’re interested in, the cost of cooling your home can vary from a few hundred dollars (for a portable air conditioner or window unit) to a several thousand dollars (to have central air conditioning installed).

The truth is that there’s no reliable way to price an air conditioning system unless you know what you’re getting. Like anything else, your best bet is to figure out what you want, and then compare prices from several different retailers.

2. BTU Output

The amount of energy your air conditioner puts out is measured in BTUs or British Thermal Units. In order to decide on how many BTUs your air conditioner should have, you need to figure out how much space (in square feet) you’ll be trying to cool.

You can easily measure the square footage of a room using a tape measure, but unless your room is a perfect rectangle, don’t forget to account for all of the entrances, closets and any other nooks and crannies the room might have.

2. Square Footage BTUs Required

700 – 1,000 18,000

1,000 – 1,200 21,000

1,200 – 1,400 23,000

1,400 – 1,500 24,000

1,500 – 2,000 30,000

2,000 – 2,500 34,000

Although this chart is a good general guide to BTUs needed, there are other variables that will contribute to the way a room gets cooled. These include the following:

a. Room Occupancy

As a result of body heat, the number of people that are in a room will contribute to how warm that room is. The chart above budgets for two people in a room. Although it is not an exact measurement, basically for each additional person in a room, add 600 BTUs to your calculation.

b. Heat from Appliances

If you’re planning on using an air conditioner to cool your kitchen, the heat from the oven, range, or microwave should also be factored into the overall temperature. An extra 4,000 BTUs should compensate for this added warmth.

c. Shady or Sunny?

If the room you’re cooling gets a large amount of sunlight (like an indoor porch or sunroom, naturally) or a very small amount of sunlight (a basement or rec room), you can add or subtract 10 BTUs from your calculation.

d. Other Factors

Additional factors which can contribute to necessary BTU output to cool a room include high ceilings, quality of insulation, and types of lighting used.

3. Controls

Something else to take into account when deciding on the type of air conditioner you want is the type of control you want to use. For example, central air conditioning is usually connected to your thermostat, and once you’ve set your ideal temperature, you’ll be able to leave it alone, and the system will do all of the work for you automatically.

Other units such as portable or window units do not respond automatically, meaning you need to monitor them by hand. This can include everything from manual dials to digital keypads to remote controls.

As we’ve mentioned above, one of the major benefits of ductless split systems is the ability to cool different rooms or “zones” at different temperatures. If your whole family is spending time in one part of the house and the rest is empty, it doesn’t make much sense to be cooling the entire thing.

4. Plug Types

Because of the amount of power many air conditioners use, a lot of them won’t be compatible with standard wall sockets. Many of the smaller portable and window units will use standard 120-volt plugs, but many larger units will use 240 or 250-volt plugs, which require special outlets.

Before you purchase an air conditioner, check the plug to see if it looks like a standard plug or more like the large plug that you see on your dryer cable. This is often the case with air conditioners that are putting out more than 15,000 BTUs.

If you are purchasing one of these larger units, you’ll need to have an electrician install a special outlet for you, with a dedicated circuit to power your air conditioner.

5. SEER and EER Ratings

Every air conditioner you look at will have a SEER or EER rating. These stand for Seasonal Energy Efficiency Ratio and Energy Efficiency Ratio, respectively.

Both of these ratios are calculated by dividing the cooling output (in BTU) by the energy input (in watt-hours) under certain conditions.

The difference is that EER is calculated at 95 degrees Fahrenheit, giving you a sense of your air conditioner’s efficiency during the summertime, when people use their systems the most. The SEER, on the other hand, is based on an average of temperatures from different times of the year. Most air conditioners will list both.

Simply stated, the higher the EER/SEER rating is, the more energy efficient your air conditioner will be. In turn, units with higher EER ratings will usually be more expensive. The trade-off comes over time when accounting for your electric bills, which higher EERs can reduce.

Units that are marked with Energy Star labels are going to be manufactured according to strict guidelines which are set by the U.S. Environmental Protection Agency as well as the U.S. Department of Energy.

D. Where To Purchase Air Conditioners

Now that you’re familiar with the different types of air conditioners available to you and know what factors to consider when shopping for an air conditioner, it’s time to take the leap of purchasing the system that’s right for your needs.

For Central Air, or Through-the-Wall air conditioning systems, you’ll want to consult with an HVAC specialist or residential contractor before purchasing your system.

For window units or portable air conditioners, here is our list of online suppliers:

FUNNY: Al Bundy Buys an Air Conditioner – und die Kaiser

I admit it, I loved Married with Children TV show growing up. One of my favorite episodes is the one where Al Bundy, ever the cheapskate, buys a circa WWII air conditioner. Here’s the clip: