How to improve efficiency of portable air conditioner AC units to cool rooms faster

Portable AC units aren't as efficient as window air conditioners, but this video will provide some tips to improve your portable AC efficiency so it can more effectively and quickly cool down your garage or living space in the summer to maximize your cooling and save money.

The plastic round exhaust duct from the portable AC unit builds up and re-radiates a good amount of exhaust heat back into the room so this video will show you how to insulate the duct to prevent radiant heat from escaping back into your room allowing your portable A/C unit to cool off the space faster and more efficiently.

The video will compare before and after insulating the air conditioning exhaust duct using FLIR infrared imaging to test the effectiveness.

Below are links to products used in the video. As an Amazon Associate I earn from qualifying purchases from links marked paid.

[corygardner]

Looking through your thermal device just confirmed my personal observation of the glass on the window conducting and transferring additional heat from the outside. Might as well insulate that from the outside. Hence making your ac not work as hard to cool down your area. I don’t think other people have that point in consideration and just totally focus on the unit for the problems. Thanks for posting this video.

[ofcrfkv]

You have no idea how much this helped me!!!! 1 key word was all it took. I was on the verge of tears. THANK YOU!!!!

[zendell]

Technology Connections has a really good video about this. I rigged up an intake and output system with my single hose unit. I had a large 12" aluminum duct that covered the intake really well. I squashed the other side a bit And made a window adapter that held both the intake and output. That dramatically increased efficiency once I was no longer sucking outside air into my conditioned space, then exhausting it outside. I further improved things by covering both hoses with some cheap blankets. Kinda quieted things down, too.

Anymore I just don't feel the single hose units are worth the trouble. I have my original unit and a second one just sitting around, even in these record setting summer days.

[lexmurden]

Thanks for this. Concise, straight to the point, good useful information.

[aethel]

noticed this as well. so i also wrapped the whole exhaust with an insulator 👍
then next thing i noticed after that was solved was that the area on the window near where the exhaust was blowing was warm as well. so i stuck some wall foam stickers to cover the hole thing haha. it wasn't perfect since the foam wasnt thick (it was made for decor) but it did help.
Room has been a lot cooler now 👍👍
I'm gonna add some more insulation from the outside as well when the foam insulation i ordered arrives.

[DANWRIGHTITIS]

Great idea. I bought a machine today - was amazed at the heat coming off the tube!! I just found an old foil backed foam ground sheet in my STASH! . I cut it into 8inch sections to make it flexible & wrapped each around the tube. Its 20¨wide so just enough to go around & affixed -with the traditional GAFFER TAPE. Foil side down & white side it to the room so don´t look too bad either!! ! Definitely makes a difference. Cheers From Madrid. It´s 2am & still 28´c outside.

[mareksarvas]

I sewed a sleeve for the exhaust pipe from a thick white quilted blanket. It works perfectly.

[rachaelneslineenriquez]

There’s also the insulated sleeve you can buy and put over it! Helped mine immensely

[nosafetyswitch]

Fantastic, my mother uses one when the temperature gets really high and I couldn't fail but notice that the tube in the back is super hot essentially heating part of the room around it to an extend that i could feel it if ibstood behimd it... I will try your solution as I am sure it will improve the performance dramatically.

[jamesarias]

I also had this on my flexible pipe and it helped a little. But the best thing to add to your portable AC is a stronger blower that you put at the end of the pipe to suck out the warm air within the pipes much faster. The stronger the fan, the better the efficiency will be.

[clintwedel]

I did that a couple years ago, no FLIR so hard to prove any gains. Next thing i did was put the portable on blocks to shorten the exhaust tube as much as possible, current setup has just 6" of double thick foil/bubble insulation between the AC and window.

[RolandKontson]

Another issue is that it's removing air (also cooled) from the room. Resulting in a lower pressure, which will draw in warm air from elsewhere.

[JoMcD]

I put that exact same stuff in my window to reflect the sunlight back out. Didn't even think about using it to insulate the exhaust itself.. Here's hoping it works!

[kerrymarris]

Great common sense video, I bought a huge piece of that mylar bubble wrap at a habit restore for $50. For a 6ft roll 10-12ft long, I used it mostly to cover my van, blocks the sun 100%, great for old windows, dashboard windshield cover ..

[Sirrehpotsirch]

It is easier to purchase a box of 6" insulated ducting. It is much thicker and easier to work with. Use it to substitute the exhaust pipe that came with the A/C. Also, you can run it for longer than the original exhaust pipe.

[j___mmdcclxxvi]

Great idea, I have a unit that draws indoor air and with the thermistor monitoring the room air I was thinking of rigging the intake evap coil air from outside but not sure that would work.

[spiritwarrior]

THANK YOU for the WRAP idea 👏it WORKS !

[Pack.Leader]

I was thinking of doing this with mine. I'm using the portable unit as a last resort because my RV ac quit on me a few days ago and we are still in the middle of a heatwave in NM. I don't have the narrow roll of reflectix that you used so I am going to have to use much wider pieces and instead of wrapping and overlapping, I'll be wrapping it more like a gift. I have the metal tape so that should help. Ugh. I hate that I have to do this but we couldn't have lived had I not brought this portable thing back into our environment.
Thanks for the video and info.
Word to the wise: Don't buy these portable units, people. You're just throwing money out the window.

[spud]

You are right in recognizing that heat transfer from that exhaust duct to the space being cooled is one inefficiency of these portable AC units. But there is a much larger inefficiency that can be addressed. You mentioned that the AC unit pulls in cooled air from your garage to remove heat from the condenser coils and then pushes it out of the garage through that duct you are insulating. Stop and think. That cooled garage air that it is leaving through that duct to the outside has to be replaced from somewhere. Guess where the exiting cooled garage air is being replaced from? That's right, Your cooled air is being replaced by hot air from outside infiltrating into the garage through all gaps, cracks, and crevices around doors, windows, etc.

The solution is to add another duct (also insulated of course) going from that inlet opening in your AC unit to a second opening in that window baffle.
Ideally, you would connect the AC inlet duct to the lowest opening in the baffle, and the AC outlet duct to the highest opening in the baffle, allowing the hottest air to rise outside the window, upward and away from the lowest inlet opening, helping to minimize any potential re-circulation of hot exit air to your less hot outside air being drawn into the inlet.
Hope this helps. 🙂

[Chris-pjos]

I've installed a 4 inch "dryer vent" for a number of people to use as vents for portable a/c's. I just run them straight through stucco/siding, right at the height the hose exits the a/c unit. Then I install the a/c unit right up against the vent so that there is almost NO hose at all to emit heat. Dryer vents are louvered so no bugs/critters get in while not in use. A 4 inch cap is put in place on the inside of the room during the months the a/c is stored (winter). Less hose = less heat loss.