Results 1 to 6 of 6
  1. #1
    Join Date
    Sep 2019
    Posts
    2
    Post Likes

    What is this and where does it go?

    Hi all,
    I have an older home that currently has a mid-efficiency furnace. It has an exhaust pipe going up to what I assume is the chimney...but underneath the furnace exhaust pipe, there is a second exhaust pipe in the wall that is capped (cap comes off easily). When I look into the pipe, I can see that it clearly goes up (the same direction as the pipe above it connected to the furnace).

    My question is, what is this? Can I use an inline fan to blow the moist air out of the basement through this other pipe?

    How do I post pictures?

  2. #2
    Join Date
    Jun 2014
    Location
    Dover, DE
    Posts
    11,770
    Post Likes
    Post a photo. It’s likely a combustion air supply.
    Exhausting air is a poor method at humidity control. You’ll create a negative pressure in the basement with no make up air, and either start pulling air in from outside or conditioned air from upstairs.
    I havent failed. Ive just found 10,000 ways that wont work. - Thomas Edison

    Its not whether you get knocked down, its whether you get up. - Vince Lombardi

    "In this house we obey the laws of thermodynamics" - Homer Simpson

    Local 486 Instructor & Service Technician

  3. #3
    Join Date
    Sep 2019
    Posts
    2
    Post Likes
    Thread Starter
    overgrow.com/t/what-is-this-and-can-i-exhaust-out-of-it/22526?page=2

    The site page above has pics...cant find how to upload pics here...cant find a help section that instructs how to upload pics either.

    Thanks for the help!!!

  4. #4
    Join Date
    May 2000
    Location
    Indianapolis, IN, USA
    Posts
    40,591
    Post Likes
    Looks like an opening for an older "lowboy" furnace that was abandoned when that WhisperHeat was put in. You blow air in that you'll likely push flue gases out the draft hood of the furnace and risk poisoning everyone with CO.

  5. #5
    Join Date
    Oct 2019
    Posts
    24
    Post Likes
    Quote Originally Posted by Christappy View Post
    overgrow.com/t/what-is-this-and-can-i-exhaust-out-of-it/22526?page=2

    The site page above has pics...cant find how to upload pics here...cant find a help section that instructs how to upload pics either.

    Thanks for the help!!!
    On the comment box from the left side on 3rd number it says image click it and upload the images. Think it might help to upload photos.

  6. #6
    Join Date
    May 2018
    Location
    Elizabethtown, PA
    Posts
    97
    Post Likes
    Do not put positive pressure on any flue unless you are confident there are no combustion gasses using said flue. From the photo, I'd say there is a strong possibility there is only one flue for both the furnace and the capped inlet.

    As mentioned, the air you pull out will be replaced from outside which usually does not improve the situation. I don't believe that this is an attempt at typical basement humidity control, though.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •