There are a whole lot of air conditioning options out there, and that’s a good thing.

While a central air system is perhaps the pinnacle of humanity’s achievements in the realm of home comfort, not every home or household is in a position to get one. That’s where window and portable air conditioners come in. But these also need a way to vent—and what if you don’t have a window to do that?

There are a number of ways to vent a portable air conditioner without a window. As long as you’re able to get the heat blowing out of the space you want to cool, you’ll still get that cold breeze on a hot summer’s day. Based on your space and your DIY comfort, there’s a plan that will work for you.

Read on to learn the ins and outs of how to get your portable air conditioner working in any space!

How Portable Air Conditioners Work

In the modern age of technology that works like magic, it makes sense to wonder why we can’t just make appliances that cool down the air. Why do we need to vent hot air somewhere else?

The way all air conditioners work is that they draw the warm air from inside the house over their evaporator coils. These catch the heat’s energy in a refrigerant, and move it to condensation coils that release it. In central units, this release happens outside already. For a portable air conditioner, we need to push out that hot air.

This is why a portable air conditioner comes with a vent hose. Some users of portable air conditioners find the provided hose to be a bit short. While it’s possible to make a makeshift extension, this is inadvisable. You’ll make your AC work harder for a smaller payoff.

You also want to avoid putting too many kinks in the hose. Ideally, the air should have a straight shot from the AC unit to the exhaust location. Just like pinching off a garden hose or bending a (non-bendy) drinking straw, you can severely cut off the airflow, even if it still works. Your AC works best when physics aren’t working against it.

As long as you follow these simple best practices, your portable air conditioner can last a decade or more!

The Case of Casement Windows

The easiest way to get that hot air outside with a portable air conditioner is through a window, but if you’re reading this article, you probably don’t have one handy in the room you’re trying to cool. However, some people make the mistake of thinking that you need certain kind of window. This isn’t true.

Even casement windows can be used to vent a portable air conditioner if you’re willing to put the work in.

The way you can do this is by creating a panel that will fill in the aperture of the opened window with a space cut into it the right shape and size for your vent hose. A simple pane of plexiglass can work wonders, though anything that prevents rapid heat transfer should do.

  1. Make sure to measure twice and cut once. You want a good fit for your window frame, because any leakage needs to be patched up, or else you might lose some of that cold air to the outside or invite some creepy-crawlies into the house. This is also where you put in the exhaust hole for your vent house. Double check this work now, so you don’t have any regrets later.
  2. Carefully secure the plexiglass in the window frame. With the window open, use clamps to put up your new proxy-window in the frame. Make sure that it’s well-positioned. This is going to be up for a while.
  3. Seal off the edges with caulk to seal the window. Most of the climate controlled air in our homes already leaks through windows. A poor seal only amplifies this problem. Save the headache and the budget by heading this off now.
  4. Pop on the vent hose. You’ve done it! Secure the vent hose to the exhaust port and fire up the AC. Congratulations! Enjoy the well-earned cool.

Options Beyond Windows

Let’s face it, sometimes you just don’t have a window you can use to vent an AC. Does that mean that you’re doomed to a summer of sweltering heat without reprieve? Of course not! There are plenty of ways you can use your portable AC even without a window.

  • Vent it through your sliding doors: This option is so common that nowadays a lot of portable air conditioners are sold with an adaptor kit just for this. Effectively, this lets you put up an extra bit of wall in those last few inches of where your door normally slides to close. This frame runs alongside the normal door frame, but lets you vent out your excess heat.
  • Vent it through your doggy doors: While Fido might object to his private entrance being taken away, he’ll be thanking you once the cool benefits become obvious. Pet flaps are a built-in vent a lot of homes already have set up! Just be sure to get a good seal.
  • Vent it through a drop ceiling: Not every home has this option, but if you’re trying to cool down a room with a drop ceiling, you can vent the hot air up through it. Make sure you have circulation to an outside wall, or else you’re just making a pocket of heat that will keep your house warm. Keep an eye on the vent space: excess heat and moisture could encourage mold.
  • Vent it through the wall: If there’s no window in your room but you need to get that heat out, the idea of just cutting a hole to the outside has a certain elegance. Before you start, make sure you know where wires, ducts, studs, pipes, and any other hazards lie. There’s no shame in getting professional help. Make sure to get a vent cover to keep your home secure from pests.
  • Vent it through the wall (redux): In a pinch, hot air doesn’t need to go outside. If you don’t have any other options, you can cut a hole into an adjacent room. This isn’t quite as energy efficient, and you’ll want to keep an eye on the room you’re heating, but it can be a lifesaver. For both of these wall-vents, make sure to keep the hole as small as possible. Extra space means energy loss.
Portable air conditioner near a door
You can also vent your portable air conditioner near an open door

As always, when picking the option that’s right for you, don’t be afraid to do a little extra research. Ten minutes at the computer can help you decide if it might be time to call for a little help. Cutting into your walls is never something to do without taking precautions.

Can You Vent a Portable AC through Dryer Vents?

You might well be wondering why venting through a dryer duct didn’t make the list of ways to vent your portable AC. After all, dryer vents are made to expel hot air from inside the house to the outside world. They seem perfect for the job. Looks, however, can be deceiving.

Even though it is entirely possible to vent your portable air conditioner through dryer ducts, this is not the best or healthiest way for your air conditioner to work.

It’s possible to use air vents for your portable air conditioner.. but there are better options

Remember that the simplest way to keep your portable air conditioner working well is to make sure it has a short, straight path to the exhaust site. A dryer vent manages to hamper this, because most dryer vents are significantly tighter than your vent hose.

What this means is that the AC has to blow that much harder to get the air out. Not only does this mean it doesn’t cool as well, but it wears out that much fast. It’s like trying to drink your coffee through the hollow plastic stir-stick. It can be done, but you’ll be sore by the end of it.

This doesn’t mean a dryer duct is worse than nothing. In a pinch, you definitely can get away with it. But you’ll be getting a worse cool and a shorter AC lifespan than you would with other methods.

Are There Portable Air Conditioners Without Ducts?

Technically, there are no air conditioners that don’t require venting. However, there is a special class of climate-modifying device known as evaporative coolers. People often refer to these as swamp coolers. These appliances don’t need any ductwork or exhaust pipes to work.

An evaporative cooler uses the evaporation of water to pull heat out of the air to cool it down. In low-humidity environments, these can have a noticeable effect. However, at the end of the day, no swamp cooler rivals any vented air conditioner in its cooling power.


There’s an air conditioner for every household and every room that needs one. Even without traditional means of venting, a portable air conditioner can fill your cooling needs if you put in a little work. Next time you’re looking to cool down a room, keep these options in mind!

Thank you for checking out this article! For other appliance tips, consider checking out our related articles below!