Windowless Air Conditioner

Windowless Air Conditioner -What Are Some Options?

What do you do for AC when you do not have any windows?

What kind of air conditioner would qualify as a windowless air conditioner?

This is a problem that can come up when you are using a renovated basement as a living space.

It can also be an issue when you are in a room that is inside of another room.

For instance, my family recently built a separate closed in shop inside our garage to use as a crafting area and a studio area to record music and videos in.

The walls of the shop consist of a brick wall that leads to the outside, a wall that’s connected to the inside kitchen and two walls that are inside of the garage.

The air conditioning option that we decided on was to put a window air conditioner through one of the walls that leads into the garage.

It’s a good solution because we don’t use the garage much other than to park the cars and store tools and such.

And the heat that is exhausted from the window air conditioner goes into the garage. And it’s really not a problem. The condensation drips into a bucket.

  That’s just one example of something that can be done to get AC into a room with no windows.

There are a few options for getting air conditioning into a room that does not have any windows.

1. Through the wall air conditioner
2. Evaporative cooling
3. Mini split AC
4. Tying in new ductwork and creating a new zone in your central heat and air set up.
5. Portable air conditioning that duct into the ceiling

1.  Through the wall air conditioner.

A through the wall air conditioner can be a simple as putting a window air conditioner through the wall instead of into a window.

Another type of through the wall air conditioner is the air conditioner units that you see in a lot of hotels. These air conditioners are called PTAC air conditioning or packaged terminal air conditioning.

PTAC air conditioning require a much larger hole through the wall than a window air conditioner. But they are also commercial air conditioners that can perform well in a very large room.

The main thing you have to have for this to work is for one of the walls to be a wall that is connected to the outdoors. Or like in the example above, a wall in which you do not care whether the heat from an AC exhaust there.

Through the wall air conditioners can also be purchased as combination heater units which as you know, is perfect for the other half of the year.

2.  Evaporative cooling

Evaporative coolers come in many  portable styles that do not require a window to sit in or to exhaust heat out of.

But they do require frequent refills of water or a continuous water line connected into the air conditioner.

Evaporative coolers work better in dry climates. And are not a good ideal for areas that have a lot of year-round humidity.

And not the best solution if you have to carry the water long distances or up and down stairs.

But for apartments where there is less than adequate AC throughout the building, evaporative cooling is an option that doesn’t take any modifications to the walls or ceiling. 

In a lot of ways, evaporative coolers are the best option for a windowless air conditioner.

3.  Mini split

Mini Split air conditioners are a type of HVAC system ( central heat and air) that can be installed into a room or a whole house that doesn’t require any windows.

With this set up, there is a compressor that is installed outdoors and routed to as many rooms as you desire through external hoses.

This gives you an HVAC type effect without the cost of installing an entire HVAC system and ducting the entire house. Which can be very expensive in an already finished home.

Mini splits also give you the advantage of being able to heat the same rooms.

4.  Splitting an HVAC zone

Running ductwork to a room with no windows can be an option.

  This can work okay if you have a room where there are multiple vents that don’t warrant it.

In other words you have a room that doesn’t need as many vents and you want to route One to a different room.

I’ve seen this work where someone took the ducting off of one vent inside of a kitchen/dining area and extended it to reach into a garage that was modified to live in.

This left him with one vent in the kitchen, and one vent extending into the garage.

Which of course, left less cooling in the kitchen, but added cooling to the garage.

This is a fairly simple modification that will work to a certain extent.

Just don’t expect a huge result because you were basically taking the cooling from one room and cutting it in half to use it in two rooms.

  Don’t expect to call in a professional for this. This is definitely a gamblers project.

But it’s a fairly simple operation that you can do yourself with some duct tape, some extra duct, a sleeve to connect to the existing duct, and a new vent for the room that you’re running the duct to.

And if you don’t get the result you want, it will be pretty easy to remove it and return it back to the way it was.

5. New HVAC zone

Adding a new zone to your existing HVAC is a possibility if you have a system that is big enough to handle the extra room.

Adding a new HVAC zone will require installing a zone control panel, new thermostats, and adding zone dampers into your existing duct.

In other words, having a professional price it and do the work for you.

6.  Exhausting a portable air conditioner into the Attic.

Portable air conditioners typically require a window to exhaust the heat from the air conditioner out of.

But what if you have a windowless room that needs AC?

This idea can work if you have a room that has an attic that is connected to the ceiling.

If so, you do have the possibility of exhausting your portable air conditioner into the Attic instead of out of a window.

  The Attic is an area that is generally very warm already. And usually comes with some type of vent for the hot air to escape.

  So adding a little extra heat from the exhaust of a portable air conditioner is not going to be a problem.

This method will take a little bit of modification to your ceiling. Which if it’s done right, will look intentional and not add a huge eyesore to your room.

The idea is to put a vent into your ceiling and run the hose from the portable AC into the vent, instead of a window.

So finding a vent that matches the connection of the hose on your portable AC is going to be the best. Not only for what it looks like but for sealing it up.

Summing it up

Finding ideals for a windowless air conditioner can be a little bit of a challenge.

  The most obvious windowless air conditioner is going to be in the evaporative cooler.

Evaporative coolers do not need a window to exhaust any heat out of.

But they do require continuous refills of water.

And they do not work too well in  humid conditions.

  Some other ideals to get AC into a windowless room;

1.Put a window air conditioner through the wall,

2.Use PTAC air conditioning ( hotel air conditioners)

3.Have another HVAC zone installed.

And if you like to think outside of the box,

4.You can split an existing HVAC zone,

Or exhaust a portable air conditioner into an attic instead of through a window.

Remember, any modifications you do to  your ceiling are going to be there whether you end up using an ideal or not.

This article is in no way professional advice.

These are just things that I have seen done that will hopefully spark your own imagination, and help you get your windowless room cooled off during the summer.

Published by

Dennis Reed

Dennis Reed Owner and Author @