Through-the-Wall Vs. Window Air Conditioner: Key Differences

You need to cool a room down. You want an air conditioner. But then you go shopping, and suddenly there are two very different types in front of you, one that goes into the wall and one that goes in the window. They are similar. They do the same basic job. So what really separates them?

Quite a lot. Which one is right for you depends on your space, your living situation and how long you want to use it. This article will explain the main differences between a through-the-wall air conditioner and a window air conditioner so you can make the right call.

Table of Contents

1. What Is a Through-the-Wall Air Conditioner?

2. What Is a Window Air Conditioner?

3. Key Differences

4. When to Choose a Through-the-Wall AC

5. When to Choose a Window AC

6. Comparison Table

7. Frequently Asked Questions

1. What Is a Through-the-Wall Air Conditioner?

A through-the-wall air conditioner is installed directly through an outside wall using a wall sleeve. The sleeve is fixed in the wall, and the AC unit slides into it. Once in place, it blows cool air into the room from the front and vents heat out the back.

Your window remains totally free because the unit is wall-mounted. You can open, close, or do whatever you want with it. Installation is a little more involved than putting in a window unit, but you get a clean, permanent installation that insulates better and seals in the air tighter.

For example, the LG LT0816CER is an 8,000 BTU 115V through-the-wall air conditioner that cools up to 330 sq. ft. and includes a trim kit for a finished look. It’s a solid, no-frills option for bedrooms and other small living spaces that need a steady dose of cool.

Looking for a through-the-wall AC? Shop through-the-wall air conditioners at Varouj →

2. What Is a Window Air Conditioner?

A window air conditioner is installed in a window opening and held in place by a mounting bracket and side panels. It uses a refrigeration cycle, sucking warm air from the room, cooling it down and then throwing the heat out through the back into the open air outside.

Its appeal is its simplicity. Most people can get a window unit installed in 20 or 30 minutes with no wall work at all. At the end of the season you take it out and store it away.

Some window AC units also have a heat function, making them a practical option for all-year use. A 23,000 BTU 230V window air conditioner like the Frigidaire FHWE232WB2 cools and heats spaces up to 1,400 sq ft. It is a great choice for larger rooms that need summer cooling and some extra heat in cooler months.

Need cooling and heating in one unit? Browse window ACs with heat at Varouj →

3. Key Differences

Installation

You need to cut a hole in the wall to install a through-the-wall air conditioner, fit the sleeve and seal around it. It’s a one-time job, but it does require planning and often professional help. A window air conditioner needs no work on the wall, and most people can install one themselves in less than an hour.

Window Access

A through-the-wall unit leaves your window completely undisturbed. Use it for fresh air whenever. A window unit blocks the window the entire time it is in place, so you get the AC or an open window, but not both.

Air Seal

A through-the-wall air conditioner uses a wall sleeve that creates a tighter seal than the foam strips and side panels of a window unit. The better the seal, the less warm air sneaks back in, enabling the unit to run more efficiently throughout a full cooling season.

Flexibility

Window ACs are more flexible. You can take them from room to room when you move or store them when they are not in use. A through-the-wall unit is permanent once installed, but that’s the trade-off for the cleaner, more permanent setup it provides.

Heat Options

Both types provide heat on select models. If you want year-round climate control, look for units specifically labelled as 'through-the-wall air conditioner with heat' or 'window air conditioner with heat', and make sure the heating BTU output is appropriate for your room size before purchasing.

4. When to Choose a Through-the-Wall AC

• You own your home or have permission to modify the wall
• You want a permanent, clean install that does not block a window
• You need consistent cooling in the same room year after year
• You want a tighter air seal and better insulation than a window unit provides
• You are a landlord or property manager furnishing rental units for the long term
• You rent and cannot modify the walls
• You want something you can install yourself quickly without professional help
• You only need cooling seasonally and want to store the unit in winter
• You need flexibility to move the unit between rooms or properties
• You need both cooling and heating and want a single easy-to-install unit

5. When to Choose a Window AC

• You rent and cannot modify the walls
• You want something you can install yourself quickly without professional help
• You only need cooling seasonally and want to store the unit in winter
• You need flexibility to move the unit between rooms or properties
• You need both cooling and heating and want a single easy-to-install unit

6. Comparison Table

Here is a side-by-side look at how these two types compare:

Neither type is universally better. A through the wall air conditioner wins on permanence, air sealing, and keeping your window free. A window air conditioner wins on flexibility, ease of installation, and cost. The right answer depends entirely on your situation.

Not sure which type fits your space? Shop air conditioners at Varouj →

7. Frequently Asked Questions

Can a through-the-wall air conditioner be used in a window?

No. A through-the-wall air conditioner is designed to be installed through a wall sleeve and cannot be safely installed in a window opening. The venting is designed differently, and if used in a window, it creates gaps, making it less efficient and potentially damaging the unit.

Is a through-the-wall air conditioner more efficient than a window unit?

Yes, as a rule. The wall sleeve creates a tighter seal, which allows less warm air to leak back in. That’s a lot less work for the unit over a whole cooling season.

Do through-the-wall air conditioners come with heat?

Some are. Look for models specifically listed as through-the-wall air conditioners with heat and check the heating BTU output for your room size. Not all through-the-wall units have a heat function.

What size through-the-wall AC do I need for a bedroom?

An 8,000 BTU unit, such as the LG LT0816CER, is a good fit for a standard bedroom up to 330 sq ft. If you have a larger room, try to find something in the 10,000-12,000 BTU range.

Can a renter install a through-the-wall air conditioner?

Only if the landlord allows wall modifications, which most do not. For renters, a window air conditioner is almost always the better choice, as it doesn't require any permanent changes to the property.

Still deciding? Our team can help. Shop air conditioners at Varouj →