How To Choose & Install a Casement Window Air Conditioner Unit

How To Choose & Install a Casement Window Air Conditioner Unit

The summer heats are almost knocking on your door and you’re still wondering if you should or shouldn’t buy an air conditioner. For many people, it’s an easy question and an easier answer. But compared to them you deal with one important problem – your apartment has casement windows. This window is attached to a frame by one or more hinges at the top or at the side. It’s completely different compared to classical sliding windows and therefore to find out casements windows air conditioner isn’t an easy goal as it could look like.

Casement windows are very popular in Europe but there are spread all over the world. Our article should help people who live in a house or apartment with this kind of window and they need an appliance covering the basic requirement – not to ruin your bank account. We want to show you the possibilities you have if you make up your mind and desire to purchase an AC unit. We also try to help you with installation and present some interesting facts, tips, and tricks.

Types of Casement Windows Air Conditioners

On the market, there are lots of AC unit types that can be installed at your house or apartment. Some of them are suitable for our home but they aren’t suitable for our bank account. And we are talking about overall costs not only about a price tag.

However, machines like central air cooling systems are expensive they don’t require to be installed in a window and your issue with a casement window could be solved easily. But we dedicated this article to machines that belong to a cheap or average price category and also to units that are built in a window somehow.

  1. Window air conditioner – This appliance is installed directly in a window but you need to create a frame before.
  2. Portable air conditioner – The machine needs at least a 20-inch space on each side standing under the window.

Both types of casement windows air conditioners are suitable if you need a very well working and inexpensive machine with useful functions.

Benefits and Drawbacks of Cheaper Air Conditioners

We chose for you two types of air conditioners that can be installed in casement windows and that belong to a cheaper AC unit group.

Since the units are cheaper and easy to install you should precisely consider all the benefits and drawbacks they offer. The truth is sometimes it is much better to pay a little bit more and enjoy lots of benefits than try to save money as hard as you can and regret it.

In the comparison below there are boiled down the most important pros and cons for your better overview.

PRO TIP: Do not forget to calculate your monthly costs before you purchase an AC unit. Otherwise, you could be unpleasantly surprised by bills skyrocket.

Pros and Cons of Window Air Conditioners

If you are still unsure about the window air conditioner then you can consider the type of window air conditioner with heating function – it is a great option for those who need heating function during the winter season.

  • Cheap starting price and monthly costs.
  • You can cool only one room and don’t waste money on cooling rooms that aren’t used regularly.
  • Maintenance could be done by homeowners without having to pay for professionals.
  • Pretty quiet operation on average from 40 dB (for example it’s approximately like a quiet conversation between two persons) up to 60 dB(it’s like a loud conversation of two persons).
  • Energy efficiency labeled by Energy Efficiency Ratio (EER).
  • Hot and cold spots occur in the room regarding the unit installed in one place.
  • You have to reinstall the unit after season and store it in a dry place or buy a cover if you have to have the unit in a window during cold winter months.
  • For installation, you usually appreciate another pair of hands.
  • The window installed in a window blocks the light.

If you think window air conditioner is for you then check my quietest window air conditioner recommendations.

Or you may be interested in energy-efficient window air conditioners which save you a lot of money.

Pros and Cons of Portable Air Conditioners

  • Cheap or average starting price (depending on the functions and features) and monthly costs.
  • A very easy DIY installation you need only a window with intake/exhaust hose and an electrical outlet.
  • The unit is easy to move by strolling and you don’t need a friend to help.
  • The unit stays under the window and doesn’t block the light.
  • You need a place where to store the unit during winter.
  • The machine requires to have 20 inches around for better airflow.
  • This kind of appliance is not so energy efficient however you can reduce the consumption by using some smart function like a programmable timer or sleeping mode.

How to Choose Cooling Capacity

The cooling capacity for the casement windows air conditioner is defined by BTU (British Thermal Units). This unit indicates how much energy you need to cool the room.

If you want to buy an air conditioner you should know the BTU for a room where the appliance should be installed. To find the value of BTU you have to measure the room. According to the measure of the room in square footage find the appropriate BTU in a table below.

BTURoom Size
(in Square Footage)
BTURoom Size
(in Square Footage)
5,000 BTU150 sq. ft.14,000 BTU700 sq. ft.
6,000 BTU250 sq. ft.18,000 BTU1,000 sq. ft.
7,000 BTU300 sq. ft.21,000 BTU1,200 sq. ft.
8,000 BTU350 sq. ft.23,000 BTU1,400 sq. ft.
9,000 BTU400 sq. ft.25,000 BTU1,600 sq. ft.
10,000 BTU450 sq. ft.28,000 BTU1,900 sq. ft.
12,000 BTU550 sq. ft.36,000 BTU2,700 sq. ft.

Do not choose your new AC unit according to BTU. There are other aspects that affect the cooling capacity:

  • Since the human body heats the air you should keep it in mind. If you have a device in a room where two people live you have to add 600 BTU for every additional person.
  • If you love cooking and prefer to install the machine in a kitchen increase the capacity by 4,000 BTU regarding the heat accumulating there while cooking or baking.
  • For well-shaded rooms, it’s possible to reduce the capacity by 10%.
  • If your room is exposed to the sun for the almost whole day increase the BTU by 10%.
  • Installing the appliance in a room that is adjoined to another room while they aren’t separated by a door means adding together their square footage.

Involve these smart tips into your consideration and we make you sure you will choose a perfect unit for your home!

How to Calculate Monthly Costs

Calculating the monthly costs is crucial. However, the starting price is a big investment we should keep in mind the operating of a unit could be a significant investment every month in a season. If you overlook this price aspect you can face a problem in the future.

Let’s do an example calculation together. Parameters need for the formula:

  • How many Watts your unit consumes.
  • A price for kilowatts per hour (from your electric company).
  • A number of hours you operate your machine every day in a season.

Monthly Cost Calculation Formula:

Watts x 1 (hour of use) ÷ 1,000 x Price given by your electric company (kWH) = Cost of operating for one hour

Example of Calculation (Considering Average Price $0.1241/kWh for State Alabama):

  • (500 Watt unit x 1-hour ÷ 1,000) x 0.1241 (kWH) = $0.06205 Cost of operating for one hour
  • $0.06205 x 8 hours per day = $0.4964 Daily cost of operating
  • $0.4964 x 30 days in a month = $14.892 Monthly costs of operation a window AC unit

As you can see above the monthly cost in this example is $14.892. Use this formula to find out the overall costs and nothing will surprise you.

How to Instal the Window Air Conditioner in Casement Window

Installation of a window air conditioner into a casement window isn’t easy and requires some skills and tools. Since this type of AC machine is primarily designed for a vertically sliding window you have to prepare a special frame to install the unit on a sill.

Before you start the installation process make sure the chosen window is close to the energy outlet because the electric cord isn’t so long.

Required Tools:

  • Drill
  • 12 Long Wood Screws
  • Screwdriver
  • Saw
  • 4 in x 2 in Lumber (the length is depending on the size of the window, read the instruction before you start the process)
  • Measuring Tape
  • Plywood Scrap or Plexiglass (the plexiglass allows the light to get in)
  • A Friend (optional depending on your skills)

Step 1: Measure the Window and the Unit

Before you start you should read all the steps and consider if you will be able to make it. These instructions are pretty easy but you really need some tools and maybe you’ll appreciate another pair of hands.

We start by measuring the unit. First of all, measure the width of the machine including all vents sticking out on the side. The vents have to be involved regarding the installation. If we won’t involve them in the measurement the unit couldn’t slide in.

Measure the height of the air conditioner by using a measuring tape. The important thing is we don’t need to include the height of the lips on the bottom or on the top. For the installation process, it’s not important to know it.

Now, it’s time for the window. Open it and measure its height. Write all the three numbers on a paper.

Step 2: Prepare the Material

Take the lumbers and cut three shorter pieces long as the width of the unit is (again we need to include the vents). Cut another two pieces long as the length of the unit is (again we do not involve the lips).

The result of this step is five pieces of lumbers.

Step 3: Frame

Take two shorter and two longer lumber and create a frame. Use two long wood screws at each connection point. When you are ready try to fit the frame in a window. It wouldn’t be good to keep going if you make a mistake.

If the frame is a bit loose we can fix it then by using a wedge or a foam.

Step 4: Top of the Frame

Now, put the frame on a floor in a stand-up position. Take the unit and put it in a frame very carefully. The bottom and top parts have to be aligned with the frame. Put the last shorter lumber on the unit and mark the position of the unit.

You can take the machine and put it away. Screw the lumber into the frame on a position you marked.

It’s time for installing the plywood or plexiglass. Cover the hole in the frame by using the plywood. Fasten it on a position by using screws. If you need to open the window during summer months use hinges on one side.

Step 5: Assembling

Slide the frame in a window. If it’s too lose you have to fix it by using foam or wedge. Now, lift the unit and slide it in the frame. Fasten the machine by using one or two screws into the lips. Make sure there are no gaps around. If you find some of them it’s crucial to fill the gaps.

Plug the cord in the energy outlet and turn the appliance on.

How to Install the Portable Air Conditioner in Casement Window

If you decided to buy a portable air conditioner the installation in a casement window is easy. It’s easier than the installation process of a window AC unit. This type of machine is usually provided with an installation kit for a sliding window. A part of it is a window panel. We won’t use this panel. Instead, we need a window sealing with zipping and adhesive fastener.

Also, you don’t need help from a friend. You can do it yourself.

Required Tools:

  • Window Sealing with Zipping and Adhesive Fastener
  • Knife

Step 1: Preparation

Our first advice is very important. Find out if the window you have chosen for installation is close to the energy outlet because the cord is usually pretty short. Another very good tip is to have the machine under a window where aren’t obstacles or objects that can worsen the airflow. Remember you should keep at least 20 inches on each side.

Step 2: Assembling

Take a hose and screw the diffusers on each end. Then, insert and slide the vent hose assembly into a hole on the back of the unit (if on the back there is a circular connection rotate the circular vent hose counter-clockwise). You need to snap it in place.

Step 3: Window Sealing

Attach the adhesive fastener tape. Paste the tape along the frame. Trim the tape by using a knife and connect the tapes around the frame. Fasten the window seal starting from the middle. Make sure that both sides are aligned.

Step 4: Connect the Sealing

Unzip the sealing and insert the end of the hose. Zip the sealing. Plug the machine into an energy outlet and turn it on as a double-check everything works well.

The Bottom Line

If you have casement windows at home and need a great AC unit in a cheap or average price category this article gave you a better overview. We summarized all important casement windows air conditioner facts.

For those who desire to control monthly costs, we added a calculating formula that helps you to find out the overall costs. As a great tip on how to choose the AC machine, we took a closer look at defining a cooling capacity along with smart tips and tricks.

All who have already bought a portable or window air conditioner and are looking for a complete guide on how to install the unit in a window we boiled down detailed instructions step by step. Everything you want to know about a cheap air conditioner in a casement window in one place!

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