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Vent piping advice

MichaelT
MichaelT Member Posts: 32

I'm deciding how best to terminate my vent piping through the roof for my navien nhb-150H. Is a tee for the exhaust and U bend for the intake the best way to do it? This is from the Navien manual. Usually I see venting with a 90 degree elbow at the end with a screen

Screenshot 2025-10-03 at 2.33.51 PM.png

Comments

  • neilc
    neilc Member Posts: 3,055

    follow the manual,

    except, that air intake, looks weird, I would expect you want the 12 inches from the bottom of the intake gooseneck, to the roof deck directly below the intake, not to bottom of rafters at the deck penetration,

    call them and ask to explain why the intake is on the deck

    known to beat dead horses
    MichaelT
  • Jamie Hall
    Jamie Hall Member Posts: 26,403

    That 12 inch minimum to the rafters on a sloping roof might work — if you never see snow and the roof is flat or nearly so. Otherwise it's just insane.

    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    nate379MichaelT
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 11,122
    edited October 3

    Do what is in the installation manual. That is the best advise. If there are several options, then select the one that you are the most comfortable with. But don't just make something up that is not in the manual because of some other piece of equipment used that design. Only use those options that are listed by the manufacturer. If for some reason you have an existing vent from an old appliance that you wish to re-use, then take a picture of that exhaust/inlet vent system and see if you can get the Tech Support people at the manufacturer to approve it. Email is the best way to do this, because you can print their reply and keep it with your I/O manual for future reference.

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

    MichaelT
  • nate379
    nate379 Member Posts: 104

    No kidding. Should be 3-4ft off the roof deck unless you regularly shovel the roof or somehow need a boiler in Florida

  • MichaelT
    MichaelT Member Posts: 32

    Yes I am in a snowy climate, Michigan, so I will be sure to have the air intake U well above the snow level