Page 1 of 2 12 LastLast
Results 1 to 13 of 21
  1. #1
    Join Date
    Dec 2012
    Posts
    9

    90% Carrier has rich gas exhaust?

    Need help

  2. #2
    Join Date
    Dec 2011
    Location
    San Antonio, TX
    Posts
    381
    Need more info!

  3. #3
    Join Date
    Jun 2003
    Location
    Chicago, IL
    Posts
    4,198
    Secondary heat exchanger is likely plugged.

  4. #4
    Join Date
    Aug 2004
    Location
    S.E. Pa
    Posts
    6,058
    you need to provide some intelligible data on this. What were the combustion analysis numbers and what is the appliance doing or not doing? How did you come to this conclusion? By *rich* what do you mean?

  5. #5
    Join Date
    Nov 2012
    Posts
    9
    Craig1 is probably correct, but you need a flue gas analysis. You needto know how much co is in the exhaust.

  6. #6
    Join Date
    May 2011
    Posts
    79
    The usual amount is 'higher PPM than my TPI is capable of reading'.

  7. #7
    If what I think you’re talking about is true I would also suspect a clogged secondary. I encountered many carriers with clogged secondary’s and the symptoms were always the same, awful smell at exhaust, extremely high ppm on my combustion analyzer.

  8. #8
    Join Date
    Dec 2012
    Posts
    9
    OK relax, here is some data. Found 4 inch filter very plugged (removed), supply temp. at 100 degrees, return temp. 70 degrees, factory spec is 40-70 delta T. Found gas manifold pressure at 3.5 inch water column. Took CO reading in house and readings were 0. Did not take readings out at exhaust. (Stupid) Did notice pressure tape fitting on gas valve on manifold side connected to combustion fresh air intake.

  9. #9
    Join Date
    Dec 2012
    Posts
    9
    Thanks for the help!! Will return and take CO readings on exhaust and let you all know the results!!

  10. #10
    Join Date
    Feb 2010
    Location
    In a boiler room
    Posts
    6,915
    Does the exhaust have a bad smell? Or what led you to believe it was rich?

  11. #11
    Join Date
    Dec 2012
    Posts
    9
    Customer was complaining, and when I arrived I could smell it. Then I went over to the exhaust and it just smelled rich to me. Hope that helps.

  12. #12
    Join Date
    Dec 2012
    Posts
    9
    Just took CO readings and it was off the scale, so i am a commercial HVAC guy, can you give me an idea how hard it is to change out a secondary heat exchanger and time involved?? (Still waiting to hear back from Carrier about warranty details)

    Thanks

  13. #13
    Join Date
    May 2012
    Location
    Upper Michigan
    Posts
    3,587
    I wouldn't bother replacing the secondary, they changed there design because it was so problematic. Last one I found with bad secondary they gave like 500 or 1500 towards a new furnace I think.

    That one smelled terrible on lp.

Page 1 of 2 12 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