How to Install a Through the Wall Air Conditioner and Sleeve: Step by Step Guide

Through the wall air conditioner is a very affordable kind of air cooling machine with not so high year operating costs. If you need an appliance offering a lot for a lower initial price these models are ideal for you. The installation isn’t a complicated process and I can make you sure you can make it. Of course, it means you can save money. Follow my guide on how to install a through the wall air conditioner sleeve and unit step by step and use my tips and tricks.

These models work on the same principle as many window AC units but when you decide for this variant you should know the installation is permanent. The wall sleeve air conditioner doesn’t need to be reinstalled after the season. So, the spot where the machine is placed is very important and it should be close to the outlet. Let’s take a closer look at the installation process step by step.

How to Install a Through the Wall Air Conditioner Sleeve

Unpack everything you need for the assembly of your wall air conditioner sleeve from the box. Double-check all of the parts with a manual. Once, you are ready we can start.

Step 1: Preparation

Before you start with the installation process, open the manual provided by the manufacturer and check what tools and parts are included. It can happen you will need some extra screws or washers. And sometimes everything is included and it would be useless to buy anything.

Tools You Need:

• Level
• Screwdriver
• Protective gloves
• Sealings

Step 2: Sleeve panels together

Take the bottom part of the sleeve and put it on the floor. Now, take one side panel and fasten them together by using screws. Once you’re ready, do it again with the second side panel.

PRO TIP: According to my experience on the bottom part there are usually arrow symbols pointed to the interior side of the in-wall AC sleeve. Keep it in mind.

Your sleeve has currently a shape of letter U. Let’s move on. Take a top panel and put it on the letter U. Fasten it by using screws. Insert the plastic clasps into the square holes (those holes are closer to the exterior side).

Step 3: Fasten the rear grill

We are almost finished. It’s time to install the rear grill. The rear grill usually isn’t a part of a box with a sleeve. But in many cases, it’s a part of a box with through the wall air conditioner. I recommend double-checking it before the purchase.

The rear grill can be a louvered rear grill or expanded rear grill. Put the grill on the backside and use screws with washers to fasten it.

Step 4: Install sleeve brackets

Take two brackets and install them on the top of the sleeve by using screws. Then, take two other brackets and fasten one bracket on each side of the sleeve.

Step 5: Slide the sleeve into a wall

I explained how to install the through the wall air conditioner sleeve. The position of the brackets can be a bit different and it depends on a model of a sleeve. Also, the manufacturer of the sleeve sometimes provides some extra screws for fastening the sides. But it’s just for your extra peace of mind.

Once your sleeve is ready, you can take it and slide it into the wall opening. Before you do it you can do a quick check the sleeve is level front to back and left to right.

Step 6: Sealing gaps

After a successful installation of your sleeve, you have to ensure there are no gaps, cracks, or remaining opening that could cause air or water infiltration. It could badly damage your unit and sleeve or reduce the efficiency of the working unit. Use a high-grade caulking product to seal every possible holes or gap.

Koldfront WTCSLV Through the Wall Air Conditioner Sleeve

Frigidaire 18 inches Sleeve for Through the Wall Air Conditioners

Keystone 26 inches Sleeve for Through the Wall Air Conditioners

How to Install a Through the Wall Air Conditioner Unit

Once you successfully installed the through the wall air conditioner sleeve, it’s time to get started with the unit. The installation process is very easy and you will use almost the same tools as you used for the sleeve one. The only thing I have to point out is to have another pair of hands to help you.

Don’t forget to follow the instructions in the manual provided with the wall sleeve air conditioner as well.

Step 1: Preparation

First of all, I have to mention you should follow the instructions in the manual and you should read my guide as additional info. The reason is every model is a bit different and some parts of the installation process could be a little bit different.

If you have through the wall air conditioner sleeve from the past and your goal is a replacement of the unit, you can skip this step. But don’t forget to double-check your new AC unit model is compatible with your older sleeve. Also, it would be perfect if you could clean the sleeve and give it back by using a good kind of new seal.

If you bought a new cooling device you should know how to install a through the wall air conditioner sleeve along with the unit. Let’s get started with the tools you will need.

Tools You Need:

• Flat screwdriver
• Screwdriver
• Level
• Drill
• Tape measure
• Protective gloves
• Sealings
• Plastic clasps

PRO TIP: I strongly recommend asking a friend for help. You will definitely appreciate another pair of hands. Do not install your new through the wall air conditioner sleeve and a unit alone!

In the manual from the manufacturer, there can be something else such as screws or putty knife. So, don’t forget to follow these instructions as well. They are here for the smooth installation process.

Step 2: Prepare the sleeve

If you desire to only replace your current through the wall AC unit, there is no need to buy a new sleeve. The sleeves are designed to fit many brands. That is awesome. But you should ensure your current sleeve is really suitable for the new unit before you buy it.

If a through the wall air conditioner sleeve needs to be installed because you are going to install the sleeve and unit for the first time, look above for the instructions. The process of assembling and installation of the sleeve is very easy and you don’t need to hire an expert.

PRO TIP: If you install the through the wall air conditioner sleeve and unit for the first time, I recommend being extra skillful when cutting the hole into the wall or hire an expert who will do it professionally. Keep in mind, it’s a hole in the wall and there is no space and time for making a mistake!

Make sure there are no gaps or remaining openings between the sleeve and wall. And it doesn’t matter if you just replaced the unit and kept the old sleeve or you’re planning to slide in the new in-wall AC unit. Always use a high-quality sealing to fill the gaps.

Step 3: Use seals on the sleeve

Our goal in this step is to use positioning seals and foam support blocks. They are attached inside of the sleeve part in order to allow the AC unit to be slid in properly and fit inside like a glove.

If you have a sleeve used from the previous AC unit, just double-check if the seals are in good condition. And of course, look into the manual of your new air conditioning unit if the position of the sealings is correct.

And if you’re unit along with the sleeve are completely new, follow the instructions given by the manufacturer to attach the sealings properly.

Let’s get started with the seals. Attach horizontally the first part of the seal on the rear grill under the top of the sleeve. Then, take two parts of the seals with the same length and attach them vertically on the rear grill next to the side panels.

Now it’s time for the foam support blocks. Attach the blocks on the side panels from the rear part to the front part next to the bottom part of the sleeve. Also, use the support blocks (sloped from the front the down to the back) on the bottom part of the sleeve. Do not overlook this step. Your unit needs to be sloped from the front down to the back in order to work properly.

Step 4: Unit must be grounded

I think it’s not needed to explain your unit must be grounded properly. It means the ground wire must be secured to the sleeve. Once your unit slides inside the sleeve, the ground wire is attached to the AC chassis to allow for grounding of the unit.

If you’re not sure about this step, follow strictly the instructions in the manual provided by the manufacturer.

Step 5: Slide the unit in the AC sleeve

The unit is ready to be slid into the sleeve. You should ensure the outlet cord is outside of the sleeve. Now, lift the AC unit and place it into the wall sleeve. You may have to wiggle your new unit a bit. Press on the front and side of the cooling machine to completely slide into the sleeve. Do every smooth gently. If it’s too heavy for you, use my pro tip below.

PRO TIP: I recommend lifting and sliding the AC machine with a partner. These units aren’t light and trust me it will be much better to do it with somebody.

Step 6: Assemble and attach the trim kit

Lay all four pieces of the trim kit on the floor. Press each piece together until it forms a rectangle. Press it gently. Keep in mind the pieces are made from plastic. The trim kit is ready for the installation.

Run the power cord through the trim kit and gently slide the trim kit over your new wall sleeve air conditioner. Snap it into the wall sleeve.

Step 7: Finish the installation

Plug the power cord into the outlet and try to turn it on. Once, the unit is operating the process of installation is finished. Congratulation. You did a great job!

Summary

The trough the wall air conditioner is a very affordable device. Also, the installation process isn’t rocket space science. I believe everybody will know how to install a through the wall air conditioner is he or she will have a guide and instructions provided by a manufacturer. Don’t waste money on hiring an expert or a team of professionals. You can do it yourself.

On the other hand, the units are usually very heavy and I wouldn’t recommend doing alone. You can ask a friend to do it as smoothly as it’s possible.