Venting A Portable AC Without Window: Top 6 Ideas!


A vent is essential for every portable air conditioner to operate properly. If there is no ventilation, the air conditioner will exhaust heated air back into your room, decreasing its cooling capacity. 

So, how to vent a portable air conditioner without a window? You can vent a portable air conditioner to another room or outside through walls, chimneys, doors, etc. Moreover, you can also use a “ventless portable air conditioner” that doesn’t technically cool the room like a conditioner but does help you feel cold.

Click here to check out one of the best ventless coolers available on Amazon. And continue reading to learn how to vent a portable air conditioner without a window and more in detail.

Do All Portable Air Conditioners Need To Be Vented Outside?

In short, all portable air conditioners need to be vented outside; otherwise, the air conditioning won’t be effective in that room. However, the way to vent isn’t limited to windows, as there are several options, like doors, ceilings, and walls.

As long as you can find another way to vent the heat outdoors, portable air conditioners don’t need a window.

Yes, venting it via a window is the most typical route. However, other options exist, like venting through a wall, door, dryer vent, and even in the attic. Moreover, you can also use Ventless AC units that offer cooling without the requirement of venting them.

Is Venting Required For A Portable Air Conditioning Unit?

You can use your portable air conditioner without venting the heated air. However, that makes the air conditioner’s cooling effect ineffective.

Air conditioners utilize a cooling substance that absorbs heat and circulates cooled air. 

This process generates heat, which is supposed to be released somewhere and typically transferred as exhaust.

That warm air won’t leave the space if it isn’t vented outside, neutralizing the new chilly air.

It is, therefore, essential to use a hose to exhaust the warm air from a portable air conditioner outside.

Should You Vent A Portable Air Conditioner To Another Room?

You can vent a portable ac into another room of your house if venting outdoors is not possible. However, it won’t be as effective as a portable ac that is vented outdoors because the heated air is still inside the house, causing inefficient cooling. 

Two Major Challenges:

  • Moisture Build-Up in the discharge room.
  • Overall, ineffective functioning because air is still present in the house.

Air conditioners aggressively remove moisture from the cold room and supply it to the heated space. Therefore, dehumidification is one of the key characteristics of air conditioning.

The air in the discharge chamber can already be significantly saturated with moisture, and the air entering from the discharge chute will only contribute to this saturation. So as a result, mold issues can occur from prolonged usage.

Moreover, the inner walls of houses are rarely insulated, so the walls between the cooled room and the newly overheated room will transfer heat back to the cooled room.

Additionally, air leaks will return some heated air. This will not completely negate the cooling effect but will lessen the value and efficiency, as the heated area will be considerably warmer than it would have been otherwise.

In short, this method has some downsides, like moisture build-up in another room and ineffective cooling. Hence, it is not usually a good idea to vent a portable ac to another room. But if you can deal with the associated problems and have no other choice, you can try.

Here’s How To Vent A Portable Air Conditioner Without A Window:

#1. Venting Via A False Ceiling

Majority of the portable air conditioners have a tube to aid in the ventilation process. And it will be to your advantage if you have a lengthy exhaust tube. And even if you don’t, you can create an extension to assist you with this procedure.

  • So, to do this, a false ceiling will be required.
  • Remove a tile from the false ceiling and run the tube from one room to another.
  • If you wish to create absolute isolation, you can cut the tile so it fits snugly around the tube.

Indeed, this is an excellent method for venting portable air conditioners into another room. It will allow you to route the exhaust tube over a long distance without disturbing the basic elegance of the inside, and it will also be effective.

The only disadvantage is that you will need a false ceiling to accomplish this process.

#2. Using A Dryer Vent

Dryer vents are the tubes that extend from the clothes dryer to the exterior of a home or structure. An indoor dryer vent is typically utilized in places that lack exterior wall access.

Dryer vents are made to transfer hot air from one area to another. 

Most dryer vents are smaller than the exhaust hoses on portable air conditioners, so this venting method is usually not recommended. To put the hose in, you must use a lot of force. So, air can’t get out of the vent as easily as it can from a regular vent. 

But if this is the only thing you can do, you can try it. The design of a dryer vent is meant to help control the flow of hot air. So if there is a dryer vent near the room you want to cool, you can use it to get air into the room.

Note that your dryer needs to be able to get rid of extra hot air. The heat can build up and cause a fire if it can’t. If you want to connect your air conditioner to an existing dryer vent, you’ll also need to keep an eye on both the dryer and the air conditioner to ensure they keep working properly

#3. Through The Doors

Warm air from a portable AC must go somewhere – ideally, that’s outdoors, but it depends on where the unit is located.

Door ventilation isn’t an option in a living room or server room in the center of a building. However, if the system is near a door, you are lucky. Sliding doors are best for venting portable air conditioners.

This is so commonplace that many modern portable air conditioners include an adapter kit specifically for this purpose. This allows you to effectively construct an additional wall section in the last few inches where a door would ordinarily glide shut. This frame fits snugly with the door but allows hot air to escape.

I highly recommend checking out this portable sliding door air conditioner kit available on Amazon.

Pet owners also have another alternative. Do you have a pet door that lets your pets come and go? While they won’t be happy, it can provide temporary ventilation when running the system. The only thing to take care – ensure to seal the exhaust hose entry.

#4. Venting Up The Chimney

Sending the heated air up a chimney is another technique to vent a portable air conditioner and keep hot air out of a space without windows. This method of venting air conditioners without windows is less typical, though. 

Also, it is good to hire a specialist due to the difficulty of installing a chimney hose.

For the installation to be effective, a long hose equal to a chimney is needed. The chimney must also be fully empty.

If you think of venting a portable air conditioner through a used one, your safety is at risk.

Put the air conditioner within or below the chimney if you have a fireplace that is not in use. To adequately exhaust the heat, a vent hose can be attached to the chimney’s wall, and you can elevate the hosepipe higher.

A chimney vent is utilized in tiny dwellings when the chimney’s length is extremely short.

#5. Venting Through Wall

You can try this technique if the wall between two rooms doesn’t already have a permanent hole in it. But note that this isn’t a DIY approach, and you’ll need to engage a specialist to complete the process.

On a residential property, cutting a hole for a vent is not too difficult, but you still need to be careful around wiring, plumbing, and studs. So even though it might seem apparent, it’s a good idea to consider both sides (inside and outside) of the wall.

Wood and drywall are easily cut through, but brick or stone will be much more challenging.

In order to use this venting via wall method, you will need to cut a sizable hole in the wall between the room where the air conditioner will be located and the room that will function as a warm air refuse area. After digging the hole, run the exhaust tube through it into the other room and plaster the extra area.

This will improve isolation and allow you to vent a portable air conditioner into the adjacent room through the wall. But there are some problems with it. 

The likelihood that the warmth and moisture may seep back into your room increases if the wall is not adequately isolated. Moreover, you’ll have to take serious measures to conceal the tube in the other room.

#6. Venting Into The Attic

Another possible way to vent the portable air conditioner is to expel the discharged air into the attic. And for that, you need a long exhaust tube, and also you have to make the necessary arrangements for passing the tube to the attic.

There are downsides to this method, though, like mold problems in the attic and inefficient cooling operation. That said, if you have no window in the room and are really frustrated with how to vent the portable ac – try venting it into the attic.

What Are Ventless Air Conditioners?

The Ventless Air Conditioners are like ACs, but they cool by evaporation instead of the refrigerant cycle used by ACs. And they don’t need to be vented. 

Ventless coolers produce a breeze that cools us but does not reduce the temperature overall. If you are standing in front of the cool breeze, you will feel colder, but the actual temperature will remain unchanged; your perception of the temperature will alter.

A portable air conditioner that doesn’t require ductwork to function relies on evaporative cooling. These setups can function with just the presence of water and electricity.

Despite having “air conditioner” as part of the name, ventless portable air conditioners are not, in reality, air conditioners. Normal air conditioners draw in hot air from the room, filter it, and dehumidify it before recirculating it.

However, ventless air conditioners can’t remove indoor heat because they don’t have an exterior compressor. The Ventless air conditioners are referred to with different names like “evaporative coolers” and “swamp coolers.”

Here are some pros and cons of ventless portable air conditioners:

Budget-FriendlySlower Cooling
Less MaintenanceUnsuitable For Humid Areas
Sustainable And Energy EfficientBest For Only Cooling Small Spaces

In short, a ventless portable air conditioner isn’t technically an air conditioner, 

The machine blows natural water-evaporated chilly air (not refrigeration cycles that occur in air conditioners). Therefore, to be cool, we must face the evaporative cooler.

Evaporative coolers don’t have vents. And no heat exchange means the sole input is power (electric input). Some electricity is used to create cooling and airflow (which cools us if the airflow is directed toward us). Still, heat is also generated (usually as the backside of the evaporative cooler). 

In addition, heat is lost because of the inherent inefficiency of all mechanical systems. These heat losses eventually raise the room’s temperature.

That said, you won’t notice a thing about the name when you’re enjoying the cool, refreshing air it provides.

What To Do If No Venting Method Works?

In short, the best option to vent your portable air conditioner without a window is via sliding doors or ceilings. And if that’s not possible, check out the ventless air conditioners. However, if nothing works, you can also use desktop or floor-standing fans as the last resort. They’ll send a refreshing wind your way to help you relax.

You can spray yourself with water which will provide even more relief from the heat. With all that said, during a heat wave, fans just serve to spread the stifling warmth throughout the room – and that’s when you’ll feel the need for a portable air conditioner.

Aron Blake

I am the lead copywriter on Homezesty and the Webmaster. I have a lot of experience in home renovations and the creation of style. I enjoy writing and sharing my tips on how to create the best living environment. My Linkedin Profile, My Twitter Account

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