Return to the Heating & Air Conditioning Forum | Post a Follow-Up

How 2 properly vent windo unit whose outside is 2B enclosed area?

Posted by swampwiz (My Page) on
Thu, Mar 18, 10 at 0:54

Here is the situation. I have an old house with window units. The unit in question is actually in a dedicated window (i.e., it is not regular window, but simply a rectangular cut in the wall in which the window unit takes up all the area.) The outside of this unit is currently the carport, which will be enclosed into a garage. I also plan to put a window unit for the garage itself to use during summer nights (with its metal only roof, the garage is going to be far too hot to keep cool during the day, and I can easily do what I want to do there at night.)

Anyway, obviously I need to somehow have the current window unit in question vent to the outside. The top of this unit is only about 1-1/2' from the carport/garage roof, and it is in a corner, so there are 2 walls already there. It seems that I should be able to build a small enclosure of OSB or metal duct (or maybe flexible duct?) for the base and the 2 walls up to the roof, and then cut a rectangle in the roof, and then put some type of duct out to keep the rain from coming in. I suppose that it could be a good idea to put some type of fan there to get enough ventilation as well. Then there is the question of how much headroom there should be in front of the outside of that unit.

I probably should take a picture or make a drawing, but I hope I have explained it properly. Of course, there is another window for that room that I could move the unit, but I would like to keep it open for aestethics (it is a front window) and to allow full ventilation of the room when the A/C would not be on (there is only one other easily operable window which is on the other side of that room.)

Follow-Up Postings:

RE: How 2 properly vent window unit whose outside is 2B enclosed

Frame a hole in the garage wall and install it semi-permanent like I did for my daughters art studio in the corner of the garage.

RE: How 2 properly vent windo unit whose outside is 2B enclosed a

The garage will be a real inferno during the day with a metal roof and a unit dumping even more heat into the garage (remember it is moving all the heat taken from the cooled area plus the power of the unit itself).

If the house is frame it is not hard to open under a window to put a sleeve in to hold a unit.

Many window units have sleeve instructions.

RE: How 2 properly vent windo unit whose outside is 2B enclosed a

I'm going to have someone build a tight enclosure to fit on the outside of the unit, which will funnel into a pipe, which then will run along the rafter to the outside. Since a window unit puts out a slight pressure, the pipe would basically be like an exhaust pipe. There will also be a line for the condensate to a jug. An easy and elegant $100-150 job.

And I've decided to get a 1 ton portable unit for the garage - that way I can take it with me for my next house, and at least have a an emergency backup (for both hurricane power loss or if the central unit would go down), or even for my current house if the little window units strain under the load of a super hot day.

RE: How 2 properly vent windo unit whose outside is 2B enclosed a

Trying to duct a window unit that has a fan to basically overcome the resistance of the condenser coil will have problems hitting proper subcooling temps, which will result in minimal air conditioning, high energy consumption & premature fan and compressor failure.

RE: How 2 properly vent windo unit whose outside is 2B enclosed a

It's not going to work. That fan is not an exhaust fan.

Put the thing in a different window.

RE: How 2 properly vent windo unit whose outside is 2B enclosed a

The unit will self destruct in short order if it is not in free air.

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Heating & Air Conditioning Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here