If you’ve ever tried to think of a quick and easy way to get your garage cooled down in the heat of the summer months, you may have come up with the idea to put in an air conditioner. There are some options like routing your existing HVAC ductwork at home to your garage in order to get some of that cool air from your existing air conditioning system.
The other thing you can do is to install a mini-split, which will require you to punch a hole through your wall in order to run your refrigerant lines, drain, and electrical to the outside. This also involves installing a condenser outside and running new electrical to a dedicated circuit breaker panel for your mini-split system.
If you want a less complicated and easier solution than the ones I previously mentioned, a window air conditioner or portable air conditioner might get the job done. These units usually are not powerful enough to cool down your entire garage especially if your garage is not insulated, is very large, and if it is too hot. The other thing that doesn’t make it possible to cool the entire space down is that typically garages will have an exposed garage attic. This area is usually open to allow for extra storage for the homeowner.
Air conditioners that fit into a window opening are probably the easiest to install, and doing so obviously requires a window to put the air conditioner unit into. Because the install involves having the window partially open and secured that way, it introduces some issues surrounding safety and keeping potential thieves from getting into your garage.
Now, if you want an easy installation and want to avoid issues with safety with a window air conditioner unit, another convenient option may be to use a portable air conditioner and punch a hole through your wall for the vent hose. Just like the window air conditioner, a portable unit will likely not have ability to fully cool down your garage space, but it can certainly keep a small section of your garage cool and at least bring the temperature down a bit overall.
Since I had already had a portable air conditioner at home and didn’t want to go through the hassle, I decided to go with a portable unit. In order to install a portable air conditioner for your garage, you will need a vent opening through your garage wall to to the outside. With a hole in the garage wall, you can run this exhaust vent so that the hot air can be released to the outside. Look around your garage to see if there are any pre-existing openings that you can use. One example is if your clothes dryer was relocated at some point, you might have an opening already there. Then, you don’t need to drill a new opening into the wall of your garage.
A couple features of the exhaust vent that you must consider is (1) a flap that opens when the hot air is blowing out and shuts when the A/C is off, and (2) a protected opening that won’t allow critters to climb in. Both of these features ensures that rats or other animals can’t get into your garage through the vent opening. Both features together minimizes the chance of this from happening.
Some other items you’ll need are a 3/8″ hose for draining the portable air conditioner. This may or may not be necessary depending on how humid it is where you live.
You’ll also need a power drill with a boring bit that is the same diameter as your exhaust vent hose. The exhaust vent hose for my portable A/C unit was 5 inches, so I had to get a 5-inch boring bit for my power drill. In addition to the bore itself, you’ll need the necessary attachments to connect it to your drill. For me, I had a core-bit set, but had to purchase an additional 5-inch bore that was not part of my starter set.
Tools & Materials Used On This Project
Portable Air Condtioner
4-in / 5-in / 6-in Exhaust Vent Kit (choose diameter for your A/C vent hose)
Craftsman 25-Ft Tape Measure
Zircon StudSensor A100 Stud Finder
DeWalt 20V Max Cordless Drill/Driver Kit, Includes 2 Batteries & Charger
Spyder 1/2in Hex 10 High Speed Steel Hole Saw Arbor (to use with power drill)
4-in / 5-in / 6-in Spyder Rapid Core Eject Hole Saw (diameter hole for your vent hose)
Craftsman Hand Saw, 12-Inch Hacksaw
Liquid Nails FuzeIt Construction Adhesive
Bates Caulking Gun
WORKPRO 7-Inch Diagonal Wire Cutters (may be optional)
3/8″ Drain Hose (may be optional)
The initial planning stage is confirming the diameter of the plastic exhaust piping that will run the depth of the wall in the future opening. Without this pipe running through full depth of the wall, the hot air from the A/C unit would just escape into the wall, and not to the outside.
Plan the location of the opening in your garage wall. Obviously look at the inside where your portable air conditioner unit will sit and make sure the exhaust hose runs comfortably to the wall. Then, check on the outside to see where the exhaust will vent out to. Once you’re satisfied with the location, check use a studfinder to make sure you won’t run into a stud while drilling. I made this mistake by not thinking and immediately started drilling without checking for studs. Lo and behold, I ran into one, which I then had to move the spot and fix later on. Anyway, check for studs and make sure the path is clear to bore your hole.
Boring through the drywall from the inside of the garage is easy. When you get through the interal drywall, you might run into insulation, which you’ll just have to clear out of the way. Getting through the external wall is a different story. Your external wall could be wood siding, stucco, or some other material. Take your time going with the boring bit and eventually you’ll get through the wall. Your stucco may have mesh wiring, which you’ll need to cut out of the way with wire cutters.
Now with an opening through the wall, run the exhaust vent pipe through. Mark the pipe from the outside of the exterior wall to the inside of the interior wall. Then cut it with a hacksaw so that it fits exactly the full depth of the wall.
The exhaust vent kit also comes with the inside wall mount, which fits into the pipe and mounts to the interior wall. Install screws in the wall mount at the four corners. Use a level to ensure it is mounted level.
For the outside exhaust vent, it can in most cases be mounted using construction adhesive to the exterior wall. I’m mounting it to a stucco wall here, but I also added some 100% silicone caulking to the outside diameter of the exhaust vent. What I am trying to accomplish here is keeping water from the outside running down the wall and seep into the inside of the wall. In most cases, these exhaust vents are secured with construction adhesive alone.
Ensure the exhaust vent is level and allow it to fully dry. The install is mostly complete at this point. You can now connect the portable air conditioner exhaust vent hose to the vent you just installed and test it out. Ensure the exhaust vent operates like it should (opens when the A/C is on, and closes when it’s off.)
If you live in a drier climate, you may not need to drain your portable air conditioner much. However, if you live in a more humid environment, you might have to drain your portable A/C unit a lot more. It’s always possible to undo the exhaust vent, and roll your portable air condtioner to the outside where you can unplug the drain and allow it to drain out. If you have to drain it all the time and you want to install a more permanent drain, you can run a 3/8″ drain hose from the A/C drain out to the outside using a variety of methods.
Installing a portable air condtioner in my garage provided me with instant comfort while working in the garage. It was very easy to do and I didn’t have to go through the difficulty of running any new electrical wires, refigerant lines, or any other equipment. I simply just brought my portable air conditioner to the garage, plugged it in, drilled a hole through the wall to install the exhaust vent, and started using it. I will repeat however that you shouldn’t expect a portable air conditioner to fully cool your garage; it’s simply not powerful nor efficient enough to do so. But it does provide instant relief from the heat for a small area in your garage should you need it.
