Can you send air back thru an air conditioning vent?

I have a bedroom I need to cool for the summer using a small Penguin type air conditioner. I need to vent the warmer air out of the room, through a window or otherwise. Since I have side hinged windows, this becomes a chore, having to close off so much of the wedge the slightly opened window forms. Then it occurred to me, since I do not use the central air conditioning system, I could just vent the warm air into the central air system! The house uses a Unico type system, which rather than having big vent openings into the room has several small 3 inch circular openings. I would choose one of these openings to vent into and close off the other ones in the room so as not to blow the warm air back into the room but instead force it back to the main central cooling unit.

Is there a technical reason why this ought not to work? I would think the air going back would merely vent out into the garage or whereever the central cooling unit is.


Thanks all so far - a few more details... I have a big house with lots of windows that I am in for a few more months before the bank gets it back. When I had renters I had to run central air to cool the whole house, which in some summer months (Austin, TX) ran up to $700. Now I have no renters and intend to only cool the bedroom toward the evening so that I have the one cooled space in the house. The rest of the house is immaterial to me in terms of temperature, as I will make do by working in coffee shops etc when it gets too hot (around noon) to work within the house during the day. As far as Penguin type units being lousy, mine did manage to cool a hot space I had upstairs, when the main central AC alone was inadequate to the task (likely not enough vents into the room ). OK, so far it sounds as if the vent system is used passively, shutting closed those vents I do not want the warm air ported to. Since the same set of pipes in my house also used to cool the bottom floor, I c

6 Answers

  • Sean
    Lv 5
    9 years ago
    Favorite Answer

    Another option you have would be to cose off a portion of the ducting in the house that you don't plan to use. It will over pressurize the ducting but it shouldn't be so much that it blows the ducting apart at the seems. You would have to include the area in which the thermostat is located.

    Another possibility is to get a decent size sheet of plywood, cut it down to size for your window and then cut a whole in it for your portable to exhaust through. This would be your easiest option and if you knew the size of your window and where the portable condensor duct would fit you could have it done at a hardware store. You could prop your window all the way open then and not worry about it.

  • elhigh
    Lv 7
    9 years ago

    NO. That will not work.

    The AC ducting system is a closed system - and the house is part of the loop. It pulls air from inside the house, routes it through a blower, which then sends it back into the house. So you send your hot exhaust air through the vent, through the AC, and back into the house. Net result = house gets hotter. No matter how cool you make your room, you'll make the rest of the house hotter. An AC system makes more hot air than it does cool air - that's just the way the efficiencies work, there's no way around physics - so what you will eventually wind up with is

    a) a house that's hotter than you've ever experienced before and

    b) a cooked AC unit.

    Those "portable" AC units are junk. You'd be better off turning the central system back on.

  • 9 years ago

    Basics: any air you force out of the room has to be replaced by more air coming into the room. Is all of the incoming air going into the Penguin? If not, there is no (or almost no) need of any venting to the outside. (Then your system design/function is poor.) If the incoming air is the same or warmer than the exiting air you are not gaining anything.

    The Penguin's compressor must be cooled separately from the room. If this can be accomplished by warming the remainder of the house (outside your one room) and you are satisfied with that -- OK. But, you would need to use at least two of the three vents in a closed fashion. Out of one to the Penguin's compressor unit and into another from the compressor unit -- all closed off from your room.


  • 9 years ago

    It would vent to any of the areas that have branch runs from the same trunk as the ones you are venting into. There are usually large ducts coming off the plenum which feed smaller ducts which go to several areas(different rooms), which is where the vented air could end up using the method you describe. That is if the vents(registers) are supply.

    Source(s): 35+ years of construction/hvac/electrical field experience
  • How do you think about the answers? You can sign in to vote the answer.
  • gaylor
    Lv 4
    4 years ago

    first area of learn is that if the cooling followers are on below the hood (they are going to the two be on on a similar time as a/c is on) if so look on the a/c compressor if the midsection hub is moving on a similar time as a/c is on then thats approximately all you're able to do if the followers on the on the spot are no longer be confident to be certain interior the journey that they are getting skill if so that they are shot if no longer detect fan exchange and be confident(this sensor is located somwhere contained interior the coolant path on the egine and tells the followers to pass on after the coolant reaches a particular temp) if the a/c grab(center hub on compressor) isn't spinning then be confident fuses for a/c and if no longer take it in as a results of fact a/c structures on the on the spot are no longer for novices to be messing with

  • 9 years ago

    Yes its a agr

Still have questions? Get your answers by asking now.