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Whether you want to cool your office, your hotel room when traveling, or even your RV, choosing the right size of a portable A/C when purchasing one is very important.
Why?
Simple: Because an incorrectly sized portable A/C won’t cool your space efficiently.
So in short, you don’t want to spend money on an undersized unit or a too big capacity appliance-a portable A/C that is too large will not remove humidity adequately and might leave the air feeling extremely damp.
With that in mind, below is our answer to that super important question you might have been having: “What size portable AC do I need?”
What size portable AC do I need?
How to size a portable air conditioner -The basics
Now, to find the right size of a portable A/C for your house, the best way is to first determine the square footage of your room.
Now, to calculate this, you simply multiply the room length by its width.
Note that somewhere..(Make sure to measure your room correctly)
Next, you need to know that portable AC’s cooling capacity is still measured/rated in BTUs (British thermal units).
To be clear, the BTU indicates the amount of heat a unit can remove from a room- and the higher the number, the more the cooling power.
Bear in mind that as the BTU increases, so will the size and the weight of a portable A/C unit.
To cut a long story short, you want to buy a unit whose cooling capacity is perfectly sized for the area you’ll be using it in(in square footage).
What size portable AC do I need?
Below now are specific ideas on how to size a portable A/C unit(according to the quoted cooling capacity in BTU)…
5000 BTU portable air conditioner room size
Go for a 5000 BTU portable air conditioner if your room is about 150 Sq. Ft – it, in general, works perfectly for this square footage.
6000 BTU portable air conditioner room size
If you are considering a 6000 BTU capacity portable air conditioner, then be aware that it works best for rooms up to 250 Sq.Ft. big..
7000 BTU portable air conditioner room size
If you are wondering if a 7000 BTU capacity portable air conditioner will be good enough for your cooling needs, then know that it generally cools spaces up to 300 Sq. Ft. perfectly.
8000 BTU portable air conditioner room size
We recommend you buy an 8000 BTU portable air conditioner if you intend to use it in a room that is not more than 350 Sq. Ft big for optimal performance.
9000 BTU portable air conditioner room size
A 9000 BTU portable air conditioner usually cools spaces not more than 400 Sq. Ft. best.
10000 BTU portable air conditioner room size
A 10,000 BTU air conditioner tends to cool rooms that are up to 450 Sq. Ft. in size most efficiently.
12000 BTU portable air conditioner room size
A 12000 BTU portable air conditioner is recommended for spaces not exceeding 550 Sq. Ft – they cool and get rid of all humidity perfectly.
14000 BTU portable air conditioner room size
If your room is up to 700 SQ. FT, then this is the right size portable air conditioner to purchase if you want efficient results.
18000 BTU portable air conditioner room size
Is your room bigger and up to 1000 Sq. Ft in size?
If yes, an 18000 BTU portable air conditioner is your best bet.
21000 BTU portable air conditioner room size
Still on extra big spaces, we suggest you invest in a 21000 BTU portable air conditioner if the area to be cooled is up to 1200 Sq.Ft. (but more than 1000 Sq. Ft)
23000 BTU portable air conditioner room size
A 23000 BTU portable air conditioner best room size is up to 1400 Sq.Ft.
24000 BTU portable air conditioner room size
Finally, a 24000 BTU portable air conditioner normally performs great for spaces up to 1500 Sq.Ft.
Adjustments to make depending on the stated circumstances
While the above guidelines should guide you, there are some circumstances that can make you want to make a few adjustments to the above recommendations.
Let us look at the situations that may make you want to go for a bigger/lower capacity portable air con…
- If your A/C unit is to be used in the kitchen, then increase the capacity by 4000 BTUs…we all know that kitchens get a little hotter, especially during cooking
- If your room is heavily shaded, you will need to reduce capacity by about 10 percent- shaded rooms cool a bit more easily since sun rays do not get direct entry
- In contrast, if your room is very sunny, increase capacity by 10 percent as the lack of shading means more heat to eliminate
- If the room is occupied by more than two people (regularly), add 600 BTUs for each additional person…that is the best way of guaranteeing maximum cooling for each person
Portable air conditioner size chart (portable ac size chart in summary)
| Room size (sq. feet) | Recommended BTU capacity |
| 150 sq. feet | 5000 |
| Up to 300 sq. feet | 6000 |
| Up to 350 sq. feet | 8000 |
| Up to 400 sq. feet | 9000 |
| Up to 450 sq. feet | 10000 |
| Up to 550 sq. feet | 12000 |
| Up to 700 sq. feet | 14000 |
| Up to 1000 sq. feet | 18000 |
| Up to 1200 sq. feet | 21000 |
| Up to 1400 sq. feet | 23000 |
| Up to 1500 sq. feet | 24000 |
What size portable AC do I need? – FAQs
Can portable ac units be used without a window?
Yes. You can use your portable A/C without a window.
However, because the warm air needs to be vented out, you must look for other options to vent your room like venting through the wall, the ceiling, or the door depending on what is convenient for you.
What will happen if I don’t vent my portable air conditioner?
If you run your portable A/C without a vent, it could end up heating up more than it cools because of two reasons:
- The warm air will still stay in the room.
- You will likely be feeding your A/C with recycled hot air.
Portable A/C unit sizing – Final words
Anytime you want to purchase a portable A/C, be sure to match your space’s square footage and the recommended BTUs according to the guidelines in this article.
Don’t forget to check your manufacturer’s specific sizing suggestions as they usually vary from model to model.
PS: You can shop for the best portable conditioner depending on BTU rating on Amazon
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