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Ducting

Discussion in 'Residential' started by kena, Dec 27, 2017.

  1. kena

    kena New Member

    Messages:
    770
    So... my company is doing a flip house and the manager of plumbing wanted to keep his guys busy... so he has them doing the duct work based on his design. So a 4 ton air handler needs at least roughly 1,600 cfm for the ac. He only has about 450 going out to supplies. Ugh

    So he has an 8” round coming off the main supply plenum to 4-6” round supplies. He’s not even giving those 4-6” rounds enough cfm’s .

    Anyone have any thiughts besides beating him upside the head with a take off?
     
  2. jamesyarbrough

    jamesyarbrough Amateur Gynecologist

    Messages:
    3,813
    Location:
    Denison TX
    just keep quiet. Let them get what they deserve
     
    Texas-Tech, R2D2-TX and jpb2 like this.
  3. Catpower

    Catpower The Crowd Pleaser

    Messages:
    22,461
    Location:
    in the Cabana
    Tell the HVAC chief about it to get the job done right the first time,it will look pretty bad if a mechanical contractor can't do his job right and it will really hose the people who buy the house, might be their first one and they will just have to live with a shitty job
     
  4. pecmsg

    pecmsg Junior my ASS

    Messages:
    21,714
    Location:
    Eastern LI
    Why 4-Tons?
    Because he said so?

    Another flip house that’s garbage!
     
    mike1020 likes this.
  5. newtech

    newtech 636

    Messages:
    871
    Location:
    Michigan
    Only 4-6" supply's, why 4 tons?

    Did I ever tell you that I hate Plumbers?
     
    Zman likes this.
  6. doc havoc

    doc havoc A cunning linguist

    Messages:
    9,500
    Location:
    45.780245, -91.731582
    This ^^^^^^^^^^^^^^^^
     
  7. Jay 41

    Jay 41 Whole-ass

    Messages:
    141,993
    Location:
    Madiganistan
    :lachen::lachen::lachen::lachen::lachen::lachen::lachen::lachen::lachen::lachen:
     
  8. Joeysmith

    Joeysmith New Member

    Messages:
    272
    He plumbing the crapper with 1" sewer line and 1/8" supply line?
     
    Texas-Tech, GTT, Zman and 2 others like this.
  9. mike1020

    mike1020 entitled millennial

    Messages:
    18,541
    Location:
    on the roof of target
    Just put in a furnace with a constant airflow ecm
     
  10. jpb2

    jpb2 Dog Tard *

    Messages:
    47,722
    Location:
    within the bounds of reality
    That will compensate....... :). Then again the equipment gets blamed
     
    MHM serenity air and mike1020 like this.
  11. Jay 41

    Jay 41 Whole-ass

    Messages:
    141,993
    Location:
    Madiganistan
    Even if it's a "flip" house, it should need a permit, how are you getting away without manual J and D, and blower door test?
     
  12. pecmsg

    pecmsg Junior my ASS

    Messages:
    21,714
    Location:
    Eastern LI
    :lol:

    Like building inspectors know anything!
     
    Catpower, mike1020 and Jay 41 like this.
  13. Zman

    Zman Hanging by a Thread

    Messages:
    1,231
    Location:
    The "I know a Guy" State
    And order a replacement Blower motor so when it chokes itself to death!
     
    Texas-Tech likes this.
  14. frozensolid

    frozensolid Psychologist's Dream

    Messages:
    12,348
    Location:
    Earth
    Buy him a Ductulator. tell him its a late Christmas present.
     
    MHM serenity air, Catpower and GTT like this.
  15. GTT

    GTT Wannabe on a boat on a bay with a beer, & my Babe!

    The beat goes on. . . . Good grief, Charlie Brown. Technically, EVERYONE here knows what HAS to happen. It's Captain Obvious' comment you pretty much have to communicate how effed up this.
     
  16. pecmsg

    pecmsg Junior my ASS

    Messages:
    21,714
    Location:
    Eastern LI
    For general use Not to replace Manual "D"
    Duct Sizing Chart
     

    Attached Files:

    Zman and Chuck like this.
  17. kena

    kena New Member

    Messages:
    770
    It is worse to the point of no return without tearing out everything he did. The 4 ton condenser in the cellar only has 930 cfm at the return. Based on the supply cfm which I figure should be around 1600-1700 cfm, that would mean I need about 3200 cfm at the return. The existing duct work will absolutely not give the system the air it needs. I'm going to take a ductorlator Tuesday and write up an existing design vs the correct design. The owner (my boss) will never allow me to rip everything out, but there's no way to fix the cellar unit. The attic unit I have some ability to make changes before it's to late.... I hope.
     
  18. pecmsg

    pecmsg Junior my ASS

    Messages:
    21,714
    Location:
    Eastern LI
    Have a drink or 12
     
  19. kena

    kena New Member

    Messages:
    770
    The f’d up part of all this is we are flipping this house for about $2 million. Why the plumbing manager started the hvac without consulting me is a fireable offense as far as I’m concerned. To actually fix the problems could mean ripping out $20k of work and starting over. I should start doing some of his plumbing and see how that goes...
     
  20. flange

    flange Act like you care and do SOMETHING!!

    Messages:
    12,967
    Location:
    IMT--in my truck
    run one inch copper to rough in the toilet drain