How to Select a Portable Air Conditioner | Ask This Old House

Ask This Old House plumbing and heating expert Richard Trethewey walks host Kevin O’Connor through the choices In air conditioners

Cost: $100 and Up

Steps:
1. Window air conditioners install in a window and vent hot air and condensate directly out of the back of the unit.
2. Portable air conditioners sit on the floor and vent through a flexible duct. They need to be emptied to drain the condensate.
3. Evaporative coolers cool by using ice and water. They leave behind humidity.
4. Newer air conditioners may include smart functionality to allow control from a smart phone.

Resources:
Window and portable air conditioners are available at home centers.

Swamp coolers are available at home centers in the American Southwest, but are not recommended in other regions as they add humidity to the air.

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How to Select a Portable Air Conditioner | Ask This Old House

[hithere]

“Stay cool” he was waiting to say that lol

[rappsongs]

“Americans love their air conditioning”... uhh yeah, it’s 102°F outside...

[Charlesb]

Just a few important points to add about the portable A/C units and the portable Evaporative Cooling units (Swamp Coolers):
On those portable A/C, you should know they are less effective energy usage wise vs a window unit so I would suggest you only use them where installing a window unit is impossible or impractical. Also, the most common version of those portable A/C is the single hose version but it is also the most inefficient version. They make a two hose version that is more efficient but may be harder to find in your local home/DIY store but if you can find one that is the most efficient model to get.

With regard to portable evaporative/swamp coolers, these only work in areas were you have low humidity meaning they will not work in regularly humid places like the American South, for example. They will work in regularly arid places like Arizona or places like Sourthern California when the humidity is low. However, in my experience they will not cool down the room much on extremely hot days. Stay away from the small tabletop/desktop models as I have never seen those work well enough at all to be worth it.

[alexthepunk]

One thing not mentioned about the portable AC: I have that exact model they show in the video, the LG. In order for it to evacuate the heat out of the window, it has to suck air from the room. This means if you are in a small room, or an enclosed room, it will suck air and create a pressure. When I use mine, it actually sucks hot air from underneath my door to compensate for the air going out the window. The portable AC is really only good to assist a central AC, or when you need to take the edge off. (I'm in Central Florida, btw)

[mobg]

Window a/c units will always work best just choose the correct BTU

[AaronSmith-kryf]

Wish they had talked about the mini-split unit. I converted the 1 car garage in my 1960's ranch house into a man cave(Don't worry I also built a proper detached garage/workshop) Installed a Mitsubishi split unit in the converted garage, must say that thing is AWESOME. I think my electric bill is about $20 more in the heat of summer or in the dead of winter. Really happy with my small split unit heating that 26x16 space.

[livanolimanolania]

clearest explanation of those kind of units, thanks!

[wcottee]

After 60-some years of life, the one rule-of-thumb that sticks in my mind is that the size of a room air conditioner (assuming 8 foot ceilings and two windows) is Length Times Width times 32. So if the room is 20x15, the air conditioner should be 20x15x32 = 9600 BTU. I don't know why I remember this :)

[ducharmehvactraining]

the portable ac unit shown will actually put the room under negative air pressure and is much less efficient than the newer 2 pipe systems that bring in outside air for the condenser and then exhaust it the same way that the 1 pipe system does. Also, the newer units have a sling condenser fan that will pick up moisture from the dehumidification of the evaporator coil and spray it on the hot condenser to increase efficiency and then expel the moisture in the exhaust air. They will still have a bucket for excess condensation under a very humid day with a safety shut off but it isn't always needed.

[Kristina-gzwu]

I grew up with swamp coolers and I love them. I live in Colorado where its dry.

[jacquesblaque]

I've seen dual-hose portables that draw outside air AND INSIDE air to cool the condenser and get dumped outside. Some are pretty lousy at getting rid of water condensate, which could boost efficiency by evaporative cooling of condenser. Enough water collection, and the unit shuts off- don't cool no mo. Not to mention, the thin plastic hoses can dump quite a bit of heat indoors. "Window-shakers" duck those probs. Good luck!

[AdamIverson]

I absolutely do not recommend a portable air conditioner as it is so inefficient because it creates negative pressure in the room causing it to suck in heat from other room/outside and therefore, unable to cool the room as well, but consume more energy.

[MinecraftProk]

Well I love my 1980's Fedders Window Air Conditioner Unit.

[Trident_Euclid]

That last ac unit is a serious cyber security nightmare

[Engineer]

They made a major mistake by not mentioning the dual hose mobile airconditioning. Those ones eliminate a major drawback of any other mobile aircon.

[V.G.F.]

I have the same Frigidaire unit you showed and it cools like a dream. It’s pretty light too.

[elle]

Always appreciate free sound advice and tips...so thank you. I would have liked to have heard them explaining the importance of matching the square footage of a room with the BTU. It is an important part of the factor...window AC units are more efficient than the portable ones on casters.

[Davef]

Best dang video that explained all that I needed to know without the BS. They need to bring guys like them back, not diy kids

[nurseSean]

3:10 no! The water evaporating in the swamp cooler to vapor absorbs the heat! The temperature of the water is a minor factor. The heavy lifting is done by the change in state: Liquid to gas. You trade more humidity for a lower temperature.
It’s cool but it’s a moist cool.

[omegaman]

Portable ones need more watts to run as explained in another video. You are pulling air from inside. Usually a window ac 5, 000 btu runs 550 watts while a portable one runs 830 watts. Meaning higher bills and it can trip brakers if you live in a house with many people running a lot of appliances. If you can go for the wall unit.