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Portable AC Vs Window AC: Pros, Cons, & Differences

Portable AC vs Window AC

In some parts of the world, air conditioning is essential. It uses a refrigerant to absorb heat from the air and it does so, the liquid refrigerant turns to a gas which is then expelled from the AC unit.

In the case of a window AC, the unit is already outside and simple expels the warm gas out there. A portable AC includes a pipe that is normally hung out of a window when in use, and the warm air is pushed out of the window.

Both portable and window air conditioning units essentially do the same job and in the same way, but the difference is in how they are installed and potentially where they are used. This also leads to a difference in space requirements, installation needs, and the cost of the unit itself.

Read on for more information about these two basic types of AC, including the pros and cons of each, and to determine which is most appropriate for your home, office, or other space.

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Overview of the Portable AC:

portable AC
Image Credit: vwqpwv, Shutterstock

A portable AC comes with a window kit so that you can expel the warm gas out of the window, but the unit itself sits inside the property. It is portable, so it can be moved from room to room, as required, and it can be put away safely during the winter and cooler months when it isn’t required, rather than sitting and taking up valuable space in your home.

It’s also worth noting that, as well as a window kit, you can also get door kits and ceiling kits according to your exact installation needs. Because the portable AC sits within the property, it does take up space and AC units make noise, which you will be able to hear if you share a room with one.


Probably the biggest benefit of a portable AC unit is that it is easy to install. You essentially just unpack it from the box, clip the window unit in the window frame, and hang the pipe out of the window. That’s it. You can also move the unit from one room to another without having to uninstall it. Portable ACs can be installed in any room where there is floor space, even if there isn’t an external window, because you can also get door kits or ceiling kits to vent the warm gas out of these exits.

You may need to regularly empty a drip tray that collects condensation as it turns to water. Some units can be plumbed so that this water is automatically sent to the wastewater system, but this almost negates the point of using a portable unit.


Efficiency is basically the amount of space that an AC unit can cool. Some portable units will only cool a 250 square foot area but there are models that can cool a space as big as 600 to 700 square feet. Portable units are not as efficient as window units, which means that an 8,000 BTU portable AC will only be able to cool a smaller space than an 8,000 BTU window AC.

portable airconditioner
Image Credit: Adrian Schwarz, Unsplash


If you compare by power, a portable AC costs less than a window AC of equal power. You can pay around 40% more for the portable model as you would for a similar window model.

  • No installation
  • Can vent through windows, ceilings, or doors
  • The unit can be moved from room to room and even building to building
  • Costs less than an equivalent window unit
  • An internal AC can be loud and irritating
  • The AC takes up floor space
  • Not as efficient as an equivalent window unit, so you will need a higher power rating
  • The water tray needs emptying regularly


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Overview of a Window AC:

window airconditioner
Image Credit: Kamran Younus, Shutterstock

Whereas a portable AC resides within the property and vents gases out of the window or other exit point, a window AC is attached to the outside of the property on the outside of a window. The warm air passes through the unit and is expelled immediately outside. This means that the unit is housed permanently where it is installed. It isn’t portable, can’t be moved, and does require more installation.

But, window ACs tend to be more efficient and cheaper to run than portable models. You may need to check that you are allowed one on the outside of your building before having it installed, however.


Whereas there is little to no installation with a portable AC, this isn’t true of window ACs. They are heavy and need to be securely and safely fitted to a small space. Many people choose to have professional installation, which instantly ramps up the price you pay to get cool air delivered into your home or business. DIY installation is possible but it can be tricky and it may not be possible or permitted if you’re installing above the ground floor level.

A window AC generates water, in the same way as a portable unit does, but it has the advantage that the water can be left to drip because it is outside.


Like portable ACs, window ACs have an efficiency or BTU rating. Window AC units are more efficient which means that they cool a larger space than a portable AC with the same BTU power rating. Ultimately, this means that you will use less power to cool a room and it will keep your AC costs a little lower. Less power also means less noise, although this isn’t as much of an issue with a window AC because it is outside so you won’t have to listen to the constant humming noise.

Panasonic Window AC
Panasonic Window AC (Image Credit: Solomon203, Wikimedia Commons CC BY-SA 3.0)


When looking at price, it is important to either compare by power or by the amount of space the unit will cool. Window ACs cost more than portable ACs of the same power, but they are more efficient, so this cost is somewhat offset.

  • All the noise is outside
  • Takes up no space inside
  • More efficient than portable ACs
  • Cost less to cool the same space as a portable
  • Water can drip off so doesn’t need emptying
  • Cannot be moved
  • Some landlords, building owners, and homeowners’ associations won’t allow them
  • Difficult to install yourself
  • Professional installation further increases the price

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How To Decide Between Portable And Window AC

Portable and window air conditioning units are very similar. They both use refrigerant liquid to collect warm air and expel it outside. Where they differ is in how they expel the warm gas. A portable unit uses a pipe that is fitted out of the window and expels the gas, while a window unit is installed outside the window so expels the gases in the immediate area. Other differences include noise levels, efficiency, and cost.

Floor Space

Both types of AC need space, but the window AC sits outside the window and does not take up any room inside. If you have limited space in the house, and you are allowed one, a window AC is likely your best option because it leaves your floor free for things like furniture.


A window AC is a permanent installation. It cannot be moved. Therefore, it will usually only cool one room, although this may have a slight knock-on effect in the next room. A portable unit, although somewhat bulky, can be moved from one room to another, one floor to another, and it can even be taken to another building.

If you are looking to cool a single space, a window AC offers a permanent solution without the need to shift the unit around. If you find that you need to cool your bedroom at night, the living room during the day, and you may even occasionally want to cool your office down, then a portable unit is the convenient choice.


Regardless of factors like portability and even price, you may not have a choice when it comes to the type of AC you can have. Window ACs are installed on the outside of the building and some landlords, building owners, or homeowners’ associations do not allow their installation. This is especially true if you live in an apartment above the first floor where one could pose a potential hazard to those below. Check whether you have permission to install an external unit before considering a window AC.

window AC installation
Image Credit: Pixabay


All ACs make noise. In fact, they are renowned for making a constant hum. In most cases, a window AC tends to be louder than a portable model, but you hear less noise with one because it is installed outside. If you have a nearby window open, the noise may be noticeable. If constant humming noises really bug you and you want to cool the room in which you regularly sit, a window AC will meet your needs better.

Room Space

There are many different models of both portable and window ACs, including smaller units designed for smaller spaces and much larger AC units for vacuous caverns. Generally, window ACs are better able to cool larger spaces and they do so more efficiently, costing less, so if you do have a large space, a window unit would be the better option.


Similarly, there are portable and window units to meet most budgets. However, window units cost more when compared to a portable unit of the same power, and they usually have the additional cost of professional installation. They are more efficient, so will cost less to run, but you would need to check whether this fully offsets the initial cost. For a power user, the extra cost of a window unit may be offset and the increased efficiency beneficial. For occasional use, the portable AC is the more budget-friendly option.

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If you are not allowed a window AC, the decision of whether a window or portable AC unit is better is moot. Alternatively, there are benefits and pitfalls to both types, but if you want to regularly cool a large space, a window AC will prove the better option, while a portable AC is ideal if you want to cool different rooms at different times. In either case, check the power and efficiency ratings to ensure that the unit you buy is up to the task at hand.

Featured Image Credit: Left: Portable AC: vwqpwv, Shutterstock | Right: Window AC: Kamran Younus, Shutterstock


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