Page 1 of 6 123456 LastLast
Results 1 to 13 of 70
  1. #1
    Join Date
    Jun 2008
    Location
    Perry Village, Ohio
    Posts
    164

    Question Return Air problem??

    Hi, and I apologize if this is a really lame question or has been gone over many times before.

    I purchased a new home two years ago and I have been having problems with the AC in the house. The house is 3400 sq feet, has a 3 ton AC (or it may be 3.5... I forget), and no matter what we do, we can not comfortably cool our house. The front of the house faces east, and the rear of the house faces west. Lots of windows on both sides.

    The first summer we moved in, we had the HVAC contractor fix a few things. We had him adjust the fan speed as we were hardly getting any air flow on the far vents (still, we are hardly getting any air flow, but more than we were), we had him increase the return duct that attaches to the side of the furnace (when we took the cover off where the flower is, it would literally suck itself back onto the unit and I felt it was air starved and thus causing a return air flow problem.

    The problem I have is this though... I can't get my house to stay cool. Even on a 80 degree day, my house can't stay cool.

    I want to have an HVAC contractor come and fix it, but I'd like to know first off what the issue might be.

    One question I have is do I have enough return air? Right now, I calculated how many return ducts I have and I have a total of 11 ducts that have a size of 1008 square inches. Would increasing the ducts help air flow, or is there possibly an underlying issue with the return line? Most of the ducts are 14x6, and in some of the very large rooms where we have 4 or more supply vents, we only have one small return vent.

    Secondly, I do not have any noise or strong sucking by the return vents. Would this indicate that the blower fan may be undersized?

    Any help would be appreciated.

  2. #2
    Join Date
    Jun 2001
    Location
    Louisville, KY
    Posts
    12,189
    Where are you located?
    Perhaps you should have read the instructions before calling.

  3. #3
    Join Date
    Jun 2008
    Location
    Perry Village, Ohio
    Posts
    164
    North eastern Ohio... near Cleveland.

    One other issue... I'm just trying to maintain 74 degrees. With the heat we had this last weekend (mid 90's) the house just kept climbing. Downstairs was at about 79 - 80 degrees with 55% humidity and the upstairs was even warner (80 - 85 degrees depending on the room).

  4. #4
    Join Date
    Aug 2002
    Location
    Office and warehouse in both Crystal River & New Port Richey ,FL
    Posts
    18,836
    Model numbers/

    Duct sizes for return and supply at the indoor unit?

    Return grille sizes?

    Filter size and type??

  5. #5
    Join Date
    Jun 2001
    Location
    Louisville, KY
    Posts
    12,189
    Perhaps you should have read the instructions before calling.

  6. #6
    Join Date
    Jun 2008
    Location
    Perry Village, Ohio
    Posts
    164
    Thanks JR... the contractor swears that it is sized right and has gone through the Manual J and says that I should be comfortable and basically told me I was crazy. Unfortunately, I can't get him to come out when it is hot out.

    Dash, I don't have all the items you ask for, but I do have some.

    Model: Do not have with me

    Duct size for Return and Supply: Don't have with me, but I can get. The one thing I do notice though is that the supply duct splits off into two right at the start. The return is just one line though.

    Return grill sizes are all 6x14 (we have 11 of them)... total return is 1008 sq inches

    Supply sizes are a combination of mostly all 6x4 except one which is 6x2. Total 6x4 is 24 so our supply sq inches is 576 sq inches + 12 sq inches = 588 sq inches.

    With the fact that the return capacity is so much more than the supply capacity, shouldn't the air be screaming out of the vents? I have tried shutting down the registers where it is cool, and that will help the upstairs, but the rest of the house then gets too warm. It just seems that we can not balance the house out no matter what the combination is. All the other homes on my street (different builder) have everything wide open in the house and it is nice and cool.

    I'm in the process of installing window film to all the west facing windows. If in fact the AC is sized correctly, and the house has the right vents and returns, what else could be the problem? Could it be the fan speed or do I need a larger fan possibly?

  7. #7
    Join Date
    Jun 2008
    Location
    Perry Village, Ohio
    Posts
    164
    One other thing... on the return duct, we use a 16x25x1 filter, so I would assume the duct is 16x25.

  8. #8
    Join Date
    Jan 2004
    Location
    PA
    Posts
    68,776
    Quote Originally Posted by perrybucsdad View Post
    One other thing... on the return duct, we use a 16x25x1 filter, so I would assume the duct is 16x25.
    Thats very doubtfull.
    Contractor locator map

    How-to-apply-for-Professional

    How many times must one fix something before it is fixed?

  9. #9
    Join Date
    Jun 2001
    Location
    Louisville, KY
    Posts
    12,189
    There are some really good NCI contractors in your area. NCI headquarters are on the other side of Cleveland from you (ya, I looked at your IP). There are a couple of really good ones that aren't even listed on their site.
    Perhaps you should have read the instructions before calling.

  10. #10
    Join Date
    Aug 2005
    Location
    San Diego,CA
    Posts
    285
    purchased a new home two years ago and I have been having problems with the AC in the house. The house is 3400 sq feet, has a 3 ton AC (or it may be 3.5... I forget), and no matter what we do, we can not comfortably cool our house. The front of the house faces east, and the rear of the house faces west. Lots of windows on both sides.


    3-3.5 ton for 3400 sq ft??? Lots of windows on both sides? If i had to guess i would say its undersized....
    Sink or Swim!
    A Man has to know his limitations..
    To be old and wise, one must be young and dumb..

  11. #11
    Join Date
    Jun 2008
    Location
    Perry Village, Ohio
    Posts
    164
    Quote Originally Posted by beenthere View Post
    Thats very doubtfull.
    Why do you say that? Does that seem too small? The opening is almost the same exact size as the filter size. The furnace is an updraft and the return duct joins the side of the furnace box (it does not sit on a box).
    Last edited by perrybucsdad; 06-11-2008 at 12:16 PM.

  12. #12
    Join Date
    Jun 2008
    Location
    Perry Village, Ohio
    Posts
    164
    Quote Originally Posted by yorkdude View Post
    3-3.5 ton for 3400 sq ft??? Lots of windows on both sides? If i had to guess i would say its undersized....
    That's what I said, but I was told again and again that it was the correct size. In fact, I had called one local company who is very well known and the owner came out for no charge to look at the system. He also felt the compressor was sized properly. The only two things he suggested was to increase the return duct size near the blower (which the installer did) and to have dampers at the supply line (which we did). He also suggested that they increase the blower speed (which I was told by the installer they did, but it really doesn't seem like they did).

    On another note, most homes on my street are about the same size and they all have about the same number of windows and the same size compressor. If the compressor was wrong I would think everyone would be having the same problems or is that a bad assumption?

  13. #13
    Join Date
    Jun 2008
    Location
    Perry Village, Ohio
    Posts
    164
    Quote Originally Posted by jrbenny View Post
    There are some really good NCI contractors in your area. NCI headquarters are on the other side of Cleveland from you (ya, I looked at your IP). There are a couple of really good ones that aren't even listed on their site.
    Thanks JR.. I guess I should give one of them a call. I am located in zip code 44081 (eastern Lake County) so are there any that are not listed that would be closer than the two that came up? What would they do exactly? I know we are not supposed to talk about pricing, but may I ask approx what am I looking at to have someone come out and tell me what is wrong with my AC system?

Page 1 of 6 123456 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event