How to winterize a through-the-wall air conditioner

Air conditioners need to be protected in the winter and a wall unit can be especially tricky to winterize due to the way it is positioned.

Air conditioners are the perfect appliance to have when you are trying to keep your indoor temperatures as cool as possible in summer months.

Even more so when the humidity levels reach their peaks, which can make any environment uncomfortable to be in, especially a closed-off one like indoor living spaces.

When winter comes, temperatures shift and there is no longer a need for cooling. In winter, the aim is to ensure that no cold air gets into a room that you are trying to keep as warm as possible, and when this is the case, air conditioners may need to be stored away or winterized.

Preparing wall air conditioners for winter

Wall air conditioners are installed inside an opening in an exterior wall and the outside condenser (back part of the unit) is meant to be protruding on the other side of the wall to drain the AC properly.

Having a hole cut through your wall exposes a huge gap that is filled by the AC unit with added insulation to ensure there are no air leaks.

This can be a problematic setup when the winter arrives as a wall needs to be properly prepared for winter, so that you can protect it and your home from being exposed to the cold of the outside that can find its way inside through gaps between the wall unit and the wall, as well as from cold air entering the space through the vents of the air conditioner.

How to winterize a through-the-wall air conditioner

A through-the-wall air conditioner is installed in a wall opening, and it is a much more permanent installation fashion.

If you look at the similarity between window air conditioners and wall units, window units are installed in such a manner that they are easier to remove from the window, if the need arises to do so.

A good example of this is in the winter, when the unit needs to be stored to protect it from the harsh conditions of the season that can damage the air conditioner.

This is why through-the-wall units need to be winterized in order to safekeep them from cold conditions. Winterizing your wall unit is not only beneficial for the air conditioner but also for the inside of your home.

Since a wall unit is installed in a huge gaping hole, gaps can be found anywhere around the unit between the wall and the unit frame.

These gaps need to be closed with the use of insulation foam that helps to block air from leaking into or out of the space. The foam needs to be flexible so that it can easily fit through the gaps that require filling.

Look for any air leaks around the unit

A simple method you can use to be able to detect air leaks around the perimeter of the wall air conditioner is to light a lighter or burn a candle and circle around close to the unit to see if any draft is coming through where insulation foam may need to be inserted.

You will know there is a draft if the flame moves a lot more than in other spots or blows out completely. You then need to measure enough foam to cover the gap. The foam can be secured in place using adhesive or duct tape.

Buy an AC back cover for the outside of the wall unit

Since wall air conditioners are installed with the back of the unit protruding out through an exterior wall, having easy access to the back of the unit can allow for a cover to be placed on the back.

An insulation cover can help prevent cold air from entering the unit and space via the back grille of the air conditioner, and it can also prevent warm air leaking out from the draft created by the inflow and outflow of air from the back grille.

Cover the vents of the wall AC

The vents of the wall air conditioner can also be an easy airway for air leaks and the cause of drafts and heat-loss inside the home.

Fortunately, the vents can be covered with vent covers that are designed to effectively cover air conditioner vents. Vent covers come in different sizes, which makes it easy to find the right size covers for the size of your wall unit vents.

Magnetic Vent Covers on Amazon

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