So, here's the dilemma. I want to install a window unit in my garage. I know how to do this, but my wife isn't supportive of the idea because we are trying to sell the house currently. Anyways, rather than fighting this never-ending battle with her, I'm trying to see if I can somehow still use my window unit without actually cutting a hole in the wall, etc. An idea that I had was to figure out somehow how to route the exhaust to outside. This is obviously an issue because I would need an opening somewhere in my garage. Is it possible to use my window A/C unit in my garage without actually installing it in the wall? You may be able to rig up something whether the compressor-side air intake and exhaust are piped outside, but the efficiency will be low and you may risk burning out the compressor by working it too hard. If you want something you can install in a small opening, you might consider wheeled portable AC units which come with a flexible duct. If you're still determined to try it, note that window AC units have two sets of air intake & exhaust:

the "inside" side that takes air from inside (usually through a large filter on the front), cools it, and blows it back inside the "outside" side that takes air from outside, heats it (with the heat removed from the cool side) and blows it out the back. On a typical window AC unit the "outside" air comes in through vents on the side and top of the unit and is blown out the coils at the back. And they can't be the same duct, or else you will just get super hot air recirculating through the unit. You can place the whole unit outside make it water prof. Duct the (inside) which is the inflow side and the cool air to the inside of your garage. If you have an attic access in your garage you should be able to vent it to the attic. If the AC unit is expendable, try running it face down. If it tolerates that, you could set it in the attic, on boards facing down that hatch (until it falls on a buyer/inspector and gets you sued). If you could rig two ducts through your attic access, but that's going to look much worse.

Browse other questions tagged hvac air-conditioning garage or ask your own question.how to install ac unit videoEdit ArticleHow to Install an Inwall Air Conditionerscreen to cover ac unit Central air conditioning (AC) is a wonderful thing—except when it isn't practical. national ac unitYou may have a second building that needs AC, or a refurbished garage or attic that swelters in the summer. You can use the windows, but those are bulky, noisy, and cut out 50% of the window light. An in-wall air conditioner! They're quiet, efficient, and will keep you cool! Pick a location where the AC will be installed. Try not to locate above electrics and electronics because they may be damaged by condensation from the discharge air grates on very humid days.

Plan to keep the bottom of the unit 1 to 5 feet (30 to 150 cm) from the floor to minimize dust from the floor clogging the filter, and condensation forming on the ceiling. Locate the wall studs. Use a stud finder, visually inspect baseboards for nail heads, or rap on the walls with your knuckles—you can hear the sound change from hollow to solid as you rap over a stud. (Commonly, studs are 16 inches apart in the U.S.) Lightly indicate with pencil on the wall where these studs lie. Roughly indicate the layout of the AC unit on the wall, in such a way that the number of studs to be removed are minimized.Remove any molding above and below the intended opening location. Remove the drywall between those studs indicated from the floor to the ceiling first by scoring the wall with a razor blade (utility knife) along the inside of the studs. With a hammer or gloved fist, knock out just enough drywall to locate any wires or other obstructions that could be damaged with a saw.

Use of a utility knife works surprisingly well on drywall, and will result in the least amount of dust and risk of damaging wires and pipes in the wall space. To use the knife, repeatedly score the wall top to bottom. You do not need to completely penetrate through the drywall—just get through 1/2 to 3/4 of the thickness. A sharp hit on the wall with a gloved fist will break the drywall along the scored line. Alternately, you can saw out the drywall by cutting as close as possible to the side of the studs. Use of hand saws made for drywall will minimize dust. If using a Sawzall or similar, a helper with a vacuum following your cutting path will reduce dust considerably. Remove the center stud(s) if needed to accommodate the AC unit. Transfer the dimensions of the AC unit or sleeve to the inside of the outside wall. Set the placement of the exhaust opening so that the top will fall just under the edge of a full clapboard, shingle, or other siding section—wherever it will be most aesthetically pleasing (or rather, least aesthetically displeasing).

Create the hole for the outside of the unit. Mark the outside opening using a template if provided by the AC manufacturer, or draw one in. If you draw your own template, use a framing square and level to ensure that your opening is level and square. Add 1/4 inch to the height of the opening. This additional 1/4 inch will allow the unit to be angled slightly downward on the outside to prevent condensation and rainwater from collecting in the unit and leaking inside the house. If you have a specific point for the top of the opening, add this 1/4 inch to the bottom for the new line to cut. Carefully create the opening by cutting along the lines with a Sawzall.Cut a stud to fit against the two studs that make the sides of the opening created for the AC unit. Level and install at the bottom edge of the AC unit location. Cut a board to fit between the wall stud on the floor in the wall space and the bottom AC support installed in the previous step. Screw or nail these studs to the existing studs.

There should be three (possibly four if the unit is very large) new vertical studs in the space below the unit; all of which run from the bottom to the underside of the horizontal support; one in the middle, one against the existing left stud and one against the existing right stud.It will be the top of the framework for the opening. Cut two (2 x 4 construction) or three (2 x 6 construction) pieces of the same length from a 2-by. Cut one or two (again, 1 for 2x4 or 2 for 2x6 construction) strips of 1/2" plywood the same size as the 2-bys. Place the plywood strips between the 2-bys and nail or screw together. The completed header thickness should be very close to 3-1/2 or 5-1/2 inches (for 2x4 or 2x6 construction, respectively). Cut two 2-bys equal to the opening height. Secure them against the existing studs in the space for the unit, by resting on the bottom horizontal support previously installed and nail or screw in place. Rest the header on top of the vertical supports installed in the previous step.

Secure the header by nailing or screwing in place.Cut a 2-by to fit between the header and the top plate (the 2-by that the left- and right-most studs are secured to at the top) plus 1/8 inch at the left-most stud and nail or screw into place. Hammer these studs into position. Repeat for the right-most stud and for at least as many vertical studs installed in previous steps below the unit, in the space above the new header. If one stud was cut and installed in the middle of the wall space for the bottom support of the unit, then at least one (but more would be better) will be required above the opening as well. These studs above the header should fit tightly. If not a tight fit, cracks may develop on the wall surface as the weight settles on the new framework in the wall. Install any electrical outlets required while the wall is open. If the unit is high on the wall, consider installing an appropriately rated switch at this time for the outlet, as this will make powering the unit on and off easier.

It will also reduce the chance of damage during electrical storms if set to off. Put the wall back where you found it. Tape, mud (joint compound) and sand when dry. Paint wall and reinstall all molding. Install the AC unit. Remove unit front cover and screws that hold the unit inside its case. Pull the unit forward while an assistant holds the case, until it is fully withdrawn. Install the case or sleeve into the opening. Allow several inches of the case or sleeve to protrude from the wall into the room. Measure the amount of protrusion at one of the top corners, and start a screw through the sleeve or case close to this corner into the framework to keep it from moving. Move the case or sleeve in or out so that the other top corner has the same amount of protrusion. Start a screw through the sleeve or case close to this corner into the framework to keep it from moving. Repeat this procedure for the bottom corners, but remember to have the protrusion here 1/4 to 1/2 inch greater than measured at the top.

This creates a position for the case or sleeve that is tipped downward to the outside and will minimize the chance for condensation and rainwater from collecting and leaking inside. Once the case or sleeve has been tacked into position, firmly secure it by driving at least two screws into each of the four sides. Caulk around the unit. Caulk around the inside and outside of the unit by running a generous bead between the unit and the surrounding surface. Extra time spent here will ensure a seal that will help keep water out. Do not scrimp—use a high quality 30-year (or more) caulk rated for use outdoors. Make sure it is paintable. See other Wikis about installing outlets and switches for the electrical portion of your installation. An air conditioner sleeve is required for windows type units that do not allow for the removal of the air conditioner from its case. Without the sleeve, there is no way to secure the unit into the opening. When using a sleeve, references to cutting an opening to match the dimensions of AC, unit, etc. should be interpreted to the sleeve instead of the unit case.