Results 1 to 8 of 8
  1. #1
    Join Date
    Dec 2012
    Posts
    62

    Inherent failure of heat exchangers in high efficiency funaces: Myth or Reality

    I just finished reading this interesting article (somewhat dated: http://seattletimes.com/html/homegar...087_hay01.html) that basically said that high efficiency furnace heat exchangers inherently fail due to a number of reasons, but primarily lack of regular maintenance----the labor cost of that sometimes negating the savings from the efficiency.

    (Of course the exception here, which I'm ignoring, is that the DOE will soon require +90% for buyers in many locations.)


    If this is even a tiny bit true, why in the world would you want a +90% versus a 80 AFUE furnace ?

  2. #2
    Join Date
    Jul 2006
    Location
    Virginia
    Posts
    4,517
    not true ,although all furnaces should be properly maintained
    We really need change now

  3. #3
    Join Date
    Sep 2009
    Location
    Arnold mo
    Posts
    3,798
    In Missouri, I advise homeowners to put an 80% furnace in and use the money saved to air seal & insulate their home, and/or fix their ductwork, especially natural gas customers. NG is cheap and expected to stay that way.
    An answer without a question is meaningless.
    Information without understanding is useless.
    You can lead a horse to water............
    http://www.mohomeenergyaudits.com

  4. #4
    Join Date
    Dec 2008
    Location
    Ontario Canada
    Posts
    534
    I was reading this article, shaking my head wondering where this guy gets his HVAC knowledge from, then I found it, last line

    "Darrell Hay is a local home inspector and manages several rental properties."

    Just like any new technology, condensing gas furnaces HAD growing pains, but they are long gone ad were long gone in 2007. This article is %90 unjustified paranoia and %10 facts and should not be the reason you steer clear from condensing technology.

  5. #5
    Join Date
    Sep 2009
    Location
    Arnold mo
    Posts
    3,798
    The article is from 2007, I believe.
    An answer without a question is meaningless.
    Information without understanding is useless.
    You can lead a horse to water............
    http://www.mohomeenergyaudits.com

  6. #6
    Join Date
    Jun 2007
    Location
    Round Rock
    Posts
    3,412
    A 90% furnace isn't prone to failure any more than an 80% if setup and installed correctly. It does require more maintenance due to it making water when it runs, drains can get clogged up. Depending on the model of the 90%+ furnace purchased, parts can be somewhat more expensive just because there are more of them, but a higher end 80% furnace can have expensive parts on them as well. I don't particularly care for 90% in natural gas applications unless you are in areas that stay cold, I'm in Texas, so it's a waste vs. the cost. For propane, there is a savings, but if propane is what you have, you need to go dual fuel.
    I like DIY'ers. They pay better to fix.

  7. #7
    Join Date
    Jan 2009
    Location
    Keokuk, IA
    Posts
    5,520
    If anything, I'd expect little change. The HE most suspecptible to issues would be the primary HE and it's no different than the primary in an 80%. A condensing furnace for the most part is just a 80% furnace with an additional stainless steel economizing heat exchanger added to it. This gives it the benefit of lower flue gas temps so you can use PVC vent piping. THere in lies the issues. Give an installer more flexibility and they take advantage of it and you create new installation problems.

    Shrot cycling and low airflow should kill a condensing furnace just as quick as an 80%'r.

  8. #8
    Join Date
    Jan 2004
    Location
    Lancaster PA
    Posts
    66,833
    Why doesn't he mention all the popped crimp rings on 80% furnaces.
    Contractor locator map

    How-to-apply-for-Professional

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

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