Portable air conditioner

I picked up a portable a/c for my garage because the temps are so unbearable, it is a combined dual hose system. Does anyone have any suggestions on the best way to vent this without punching a hole in a wall, I live in an HOA and I am sure they would be thrilled to spot this.

I tried venting through the garage door having it cracked open at the bottom, this defeats the cooling of the shop. I thought about venting into the attic by making a hole in the ceiling, I am afraid that the rest of the house will suffer from this idea.

Do you have a window available? I recently hooked up a portable AC in the basement/shop.


I just used what I had on hand but a piece of insulation board would have a better R value than the plywood I used. If your worried about security this might not be the best option though.

Unfortunately I do not have a window.

Use the same idea as the window vent, only on the bottom of the garage door. I vent my laser that way. Just make it L shaped so it stands up while you close the door down on it. You can get a good seal when the door gasket settles onto the plywood.

This is true, I will still have heat intrusion from the top of the door. It really defeats the purpose of the A/C, for laser fumes this is not a problem.

Do you have a regular door too? If so you could craft a wedge thing much like the window thing above - a top and bottom triangle with a flat between them. You would have to keep the door against it - either with a bungie cord or something or even just leaning something against the door.

Unfortunately the only door I have in the garage leads to the house.

One last thought… you could vent through (note, not to) the attic. Up through the ceiling and either through a roof vent something like this Roof Exhaust Vent Caps VMAX-CT-4 | Ventilation Maximum, or up into the attic and back down out the soffit (if you have enough clearance to allow a duct to pass through the narrow space between the roof deck and the top of the wall) where you could install an outlet duct.

Whatever you do, make sure you are not dumping air into your attic; as you said that can (and likely will) have long term effects on the rest of the house.

There are many options out there as you have mentioned, the main problem is the shape of the hose coming off of the unit since as I stated it is a combined dual hose system. In the attached picture, the exhaust is on the left and intake is on the right.

Hmm… seems like some extra creativity may be required.

It might be possible to design an adapter that splits that duct into separate intake and return hoses (of standard size). Being able to separate them would help with efficiency as well.

You might be able to craft an adapter using your LongMill by cutting a stack of properly shaped wooden plates - another option would be 3D printing if you have big enough.

We’re into some real improvisation here. Ultimately, the easiest solution really would be to punch through the wall or garage door with the correct shape to do what you need, but those options really aren’t easily concealed (nor would you particularly want to do that anyway).

Have you got any other penetrations of the envelope of your garage? Dryer duct, central vac, etc?

Yes, creativity is definitely key in this situation, I also thought about splitting the two somehow. I do not have a 3d printer so that would be out of the question, I also do not have any other penetrations within the garage.

Without seeing the setup it’s tough to come up with ideas but, my initial thought is camouflage. I would go through the wall but on the outside, make it look like something that would be otherwise unnoticed but an HOA Karen that would give you grief.

I have to agree with @CncJim - if you can manage to craft an adapter to separate the streams, just use a standard (and unobtrusive) dryer vent for the outlet, and intake vent for the inlet.

I have thought about just installing a bathroom exhaust fan in the garage and attach the exhaust hose to the grill of the fan, the only downside is the bathroom and or dryer vents are only 4 inches.

You should be able to get 6 or even 8 inch vents, possibly used for ERV/HRV systems. Here’s a random link for example (just something I found on google, no thoughts on price or quality) https://yorktechsupply.com/shop/ventilation/vent-hood/6-inch-r2-exhaust-intake-hood-white-6-box/

I decided to return the AC, I was not going to punch a hole through my brick wall. I will just have to continue using fans and hope for cooler weather soon. Thank you to all that replied with suggestions.

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This may sound ridiculous, but on those really hot days I have the same problem. I just point the ac unit at my work station and vent back into the shop. Cold air on me is all I care about.

Many of the portable A/C units use the vent to discharge the condensation and you can only go so high vertically before water begins running back down. They typically only support 2-3’ vertical. My neighbor found this from trying to attic vent his grow room, he had water backing up into the unit and making a huge mess