Cold Air Returns

Discussion in 'HVAC' started by travelover, Feb 1, 2008.

  1. Feb 1, 2008 #1

    travelover

    travelover

    travelover

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    I'm trying to improve my home heating efficiency and am in the process of sealing my forced air ducts. In the process, I have noticed that the cold air returns from the 2nd floor to the basement are just the stud space between the outside wall and the inner drywall (no sheet metal liner). Was this pretty standard practice back in 1966 when this house was built?

    This return system seems like it would suck in a lot of cold air, plus there is no insulation in this wall cavity. Has anyone dealt with this before? Is this not a big deal in terms of heat loss?

    Thanks in advance for your thoughts.
     
  2. Feb 1, 2008 #2

    inspectorD

    inspectorD

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    Wow ...what a heat loss.
    Usually those are installed on an interior wall. Not the greatest idea regardless. I would look at a closet space or some other area to update your ductwork system.
    I am surprised you don't have any decay issues with that wall, from condensation. So what is the exterior siding made of?
    Do you have some type of insulation board on the exterior.
    What type of heating system and how old?
    Does the return air have to be connected to that room. Try getting someone in to look at "the job" and do some heat calculations.
    Or disconnect the duct and get the air from the furnace area...see what happens.:)
     
  3. Feb 1, 2008 #3

    Hube

    Hube

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    Wow!!! having return passages inside the exterior wall cavities is a complete NO-NO, unless there is a substanial thermal covering.Returns are always best on INTERIOR walls, and even back in the 1950's any sober HVAC trades person would adhere to this general rule.
    A furnace fan "drawing" return air from a exterior uninsulated cavity can sure upset a heating systems efficiency, etc.
    You would be best to "re-route" these 2 returns from the upper floor .
    If, and when you do you should also 'blow' some insulation into these outside wall cavities.
     
  4. Feb 1, 2008 #4

    travelover

    travelover

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    Brick on north side, south side is drywall because it is enclosed by attached garage .

    No


    Gas forced air, original 1966 furnace 200,000 btu


    Would that be a heating contractor? I don't see an easy path in an interior wall due to open layout of first floor



    Do you mean let the cold air return to the furnace through the open area of the interior of the house?
     
  5. Feb 1, 2008 #5

    inspectorD

    inspectorD

    inspectorD

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    I would let a pro , heating contractor, look for some solutions.
    They may try to sell you a new furnace, not a bad idea if you could. Depends on what your efficiency is now. Your ductwork needs to be eliminated from the exterior wall. You would be better off just with makeup air from the interior of the house. This is less efficient than if it where in the actual room, but better than what you have now.;)

    Then insulate that wall.:)

    The pro may find an area or show you options you do not always see. Build a small chase-way somewhere, integrated into a new cabinet or bookshelf, or.....?:D
    Good luck with your new heat bill.:D
     
  6. Feb 2, 2008 #6

    travelover

    travelover

    travelover

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    Thanks for the reply. The furnace is inefficient, but I don't think it will pay me back to replace it before I sell. Ironically, it is a nice house, but the land has appreciated so much that it will most likely be torn down when I sell. Lots of new 5000+ sq. ft. houses in the neighborhood now.

    What kind of insulation can I dump down the stud space - cellulose?

    Good suggestion. I'll noodle on this. I'm pretty handy and could do it myself, if I can find a reasonable solution. If not, makeup air would do as the neither room is used with the door closed.
     
  7. Feb 2, 2008 #7

    inspectorD

    inspectorD

    inspectorD

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    Sounds like you know your market area...good luck on the sale.
    Cellulose is fine for the cavity and installing a floor vent may be your least expensive option.

    Let us know how it works out.:)
     
  8. Feb 2, 2008 #8

    travelover

    travelover

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    Thanks. I won't sell for about 8 years, so my fingers are crossed for a real estate recovery in that time.

    I was thinking about a floor vent, as well.

    Thanks for taking the time to consider my possibilities. Amazing set of talent on this board.
     
  9. Feb 2, 2008 #9

    inspectorD

    inspectorD

    inspectorD

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    We are all here to do what we can.:)
    This place has a good feel, community wise and knowledge based. Just like the small town I live in.;)

    Your welcome.:D
     
  10. Feb 2, 2008 #10

    kerrye

    kerrye

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    Im having a different problem my heat pump works fine only problem is juast as it reach the desired temp it starts to blow cool air for about 3min befor it shuts off it will not heat up past about 74 deg what could this be?
     
  11. Feb 2, 2008 #11

    travelover

    travelover

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    kerrye, you might get a better response if you start a new thread in HVAC.
     

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