Results 1 to 9 of 9
  1. #1
    Linda Swearingen's Avatar
    Linda Swearingen Guest

    Question Popoff Drain Length?

    Is there a maximum on the length of drain allowed for a water heater pop-off valve? I couldn't find anything stating a distance limit on the water heater instructions, just a requirement to allow plenty of flow. There were only 2 elbows (a 90 just below the floor and one after exiting the crawl space wall) and no reduction in diameter, but no increase, either, and the run was over 30' before exiting the crawl space.

    Similar Threads:
    Inspection Referral SOC

  2. #2
    James Duffin's Avatar
    James Duffin Guest

    Default Re: Popoff Drain Length?

    One thing I don't see mentioned in your description is the air gap in the room the heater is in. If the relief valve discharge is not in the same room as the heater there needs to be an air gap in the room before it leaves the room.

    504.6 Requirements for discharge piping. The discharge
    piping serving a pressure relief valve, temperature relief valve
    or combination thereof shall:
    1. Not be directly connected to the drainage system.
    2. Discharge through an air gap located in the same room
    as the water heater either on the floor into an indirect
    waste receptor or outdoors.



  3. #3

    Default Re: Popoff Drain Length?

    One thing I don't see mentioned in your description is the air gap in the room the heater is in. If the relief valve discharge is not in the same room as the heater there needs to be an air gap in the room before it leaves the room.
    Depends on where Linda lives. An air gap is not required in OR.


  4. #4
    James Duffin's Avatar
    James Duffin Guest

    Default Re: Popoff Drain Length?

    Very true....I normally include "in NC" but I forgot this time. Thanks for the clarification.


  5. #5
    Join Date
    Mar 2007
    Location
    Santa Rosa, CA
    Posts
    2,476

    Default Re: Popoff Drain Length?

    Quote Originally Posted by Linda Swearingen View Post
    Is there a maximum on the length of drain allowed for a water heater pop-off valve? I couldn't find anything stating a distance limit on the water heater instructions, just a requirement to allow plenty of flow. There were only 2 elbows (a 90 just below the floor and one after exiting the crawl space wall) and no reduction in diameter, but no increase, either, and the run was over 30' before exiting the crawl space.
    Linda,

    Filling-out your profile to at least include your location can help us answer your questions better. Please do so at your earliest convenience.

    I have not been able to find any specific maximum length in the IRC (2803.6.1); however, my Code Check it states 30 feet max, but refers to the manufacturer (presumably of the water heater).

    Department of Redundancy Department
    http://www.FullCircleInspect.com/

  6. #6
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,243

    Default Re: Popoff Drain Length?

    Quote Originally Posted by Gunnar Alquist View Post
    however, my Code Check it states 30 feet max, but refers to the manufacturer (presumably of the water heater).
    The T&P relief valve manufacturer, typically Watts. The maximum length is 30 feet with 4 elbows maximum.

    That is even applies for states where the discharge is required to be in the same room or space as the water heater (i.e., such as a garage, the water heater could be in one corner and the T&P relief valve discharge could be at the opposite corner ... as long as the length was less than 30 feet and there were no more than 4 elbows.

    Keep in mind that "elbows" is not just 90 degree elbows, but includes 45 degree elbows, this is because a change in direction like that creates a back pressure resistance to the flow of the water, and the manufacturers do not want any pressure resistance, they want open to atmosphere discharge in as short a distance as possible.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  7. #7
    Linda Swearingen's Avatar
    Linda Swearingen Guest

    Default Re: Popoff Drain Length?

    Thank you to all of you. I believe I'll drop by the house and pace off the length (I can do that from outside). As it happens, I'm prohibited from quoting code here in KY, but I'm still able to note that type of problem as being a safety or fire issue. Yes, even 45's are elbows, but this one happens to have the pair of 90's.


  8. #8
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,243

    Default Re: Popoff Drain Length?

    Quote Originally Posted by Linda Swearingen View Post
    I'm prohibited from quoting code here in KY,

    Are you prohibited from quoting manufacturer's installation instructions?

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  9. #9
    Join Date
    Mar 2007
    Location
    Columbus GA
    Posts
    3,746

    Default Re: Popoff Drain Length?

    Are you prohibited from quoting manufacturer's installation instructions?

    Good point.

    ' correct a wise man and you gain a friend... correct a fool and he'll bloody your nose'.

Bookmarks

Posting Permissions

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