Results 1 to 20 of 20

Thread: Is this OK?

  1. #1
    Join Date
    Mar 2008
    Location
    Park City, Utah
    Posts
    1,530

    Default Is this OK?

    There are several things wrong with this installation. I am concerned about three water heaters connecting to one four inch single wall vent. One water heater, being used as a boiler, was 65,000 btu' and the other two were ~ 40,000 btu'. Is this acceptable or does the vent have to be larger.

    Thanks

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images

  2. #2
    Join Date
    Mar 2007
    Location
    Georgetown, KY
    Posts
    536

    Default Re: Is this OK?

    I'd be concerned that they are "T"d instead of having a Y into the pipe but the larger vent is pretty close.

    Erby Crofutt, Georgetown, KY - Read my Blog here: Erby the Central Kentucky Home Inspector B4 U Close Home Inspections www.b4uclose.com www.kentuckyradon.com
    Find on Facebook at: https://www.facebook.com/B4UCloseInspections

  3. #3
    Joshua Hardesty's Avatar
    Joshua Hardesty Guest

    Default Re: Is this OK?

    Where's the shutoff valve and expansion tank for the leftmost heater?

    Is that pex being used for the TPR line? (It *looks* like white pipe with a black crimp ring near the top, but I can't really see it)

    What's supporting that vent near the 4" pipe?

    I don't think you can lay that kind of vent flat like that.

    If the left-most heater goes out, what keeps the middle heater from venting back down the left's pipe?


  4. #4
    Join Date
    Mar 2007
    Location
    Dallas, Texas
    Posts
    4,112

    Default Re: Is this OK?

    The expansion tank appears too small for the combined capacity of the three heaters. If one is on a separate closed loop system, it would need its own thermal expansion protection. But you probably already knew that and called it in your list of other problems.

    Jim Luttrall
    www.MrInspector.net
    Dallas, Texas

  5. #5
    Join Date
    Mar 2008
    Location
    Park City, Utah
    Posts
    1,530

    Default Re: Is this OK?

    Guys,
    Thanks for all the imput. My question still remains, is that 4 inch vent large enough to handle all three heaters? The rest has been noted.

    Thanks


  6. #6
    Join Date
    Mar 2008
    Location
    Park City, Utah
    Posts
    1,530

    Default Re: Is this OK?

    The left most tank is used as the boiler for radiant heating system, it is separate from the other two. The valves are on the back side of the tank. The tpr lines are not PEX.


  7. #7
    James Duffin's Avatar
    James Duffin Guest

    Default Re: Is this OK?

    Based on Table G2428.2(1) [504.2(1)] the 4" is not large enough for the 145,000 BTU load.

    Last edited by James Duffin; 06-06-2008 at 01:02 PM.

  8. #8
    Join Date
    Mar 2007
    Location
    Hudson, WI
    Posts
    645

    Default Re: Is this OK?

    Quote Originally Posted by mathew stouffer View Post
    The left most tank is used as the boiler for radiant heating system, it is separate from the other two. The valves are on the back side of the tank. The tpr lines are not PEX.
    Check this resource especially page 14.

    As mentioned earlier, I see no expansion tank for heater being used for the radiant heat system.


  9. #9
    Join Date
    Mar 2008
    Location
    Park City, Utah
    Posts
    1,530

    Default Re: Is this OK?

    Michael,
    The expansion tank in on the floor behind the unit. No drip leg as well, like I said there were many issues with this installation

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images

  10. #10
    Join Date
    Mar 2007
    Location
    Hudson, WI
    Posts
    645

    Default Re: Is this OK?

    Quote Originally Posted by mathew stouffer View Post
    Michael,
    The expansion tank in on the floor behind the unit. No drip leg as well, like I said there were many issues with this installation
    I noticed the missing drip legs but not all areas require them. They do in my area.

    I hope that sizing chart was some help.


  11. #11
    Join Date
    Mar 2008
    Location
    Park City, Utah
    Posts
    1,530

    Default Re: Is this OK?

    James,
    Thanks for that ref. However, that table is for b vent. The four inch vent in the photo is single wall.


  12. #12
    James Duffin's Avatar
    James Duffin Guest

    Default Re: Is this OK?

    It's all I had handy....sorry! Single wall pipe would be less than the chart shows so my only opinion is that based on the chart 4" is not large enough for your load.

    I found a 1980 NC Mechanical Code Book in the basement and Table 5 Appendix B says that you need a 7" single wall pipe for your total BTU load. You could go with a 6" if you have a 15' high vent or 5" if you have a 30' high vent. This is all single wall pipe.

    Last edited by James Duffin; 06-06-2008 at 02:32 PM. Reason: More info

  13. #13
    Join Date
    Mar 2007
    Location
    Near Philly, Pa.
    Posts
    1,633

    Exclamation Re: Is this OK?

    Insufficient data provided. You need to size the common vent separately from the vent connectors. Here, I see a large B-vent all taped up with what appears to be a B-vent tee snout connector that then transitions to single walled vent connector. You use separate tables for the sizing of the connector and vent.

    There is insufficient support of the connectors.
    There appear to be 4" connectors on 3" draft hoods.
    You can manifold multiple appliances but it must meet the code sizing and bottom line, it must work . Has anybody tested this installation? Do you have other issues such as makeup air? Any signs of spillage or condensation?

    Sediment traps are ALWAYS required by code whether enforced or not.

    Bob

    Keep the fire in the fireplace.

  14. #14
    Join Date
    Mar 2007
    Location
    Spring City/Surrounding Philadelphia area
    Posts
    3,471

    Default Re: Is this OK?

    Tape used on the flue pipes is the first giveaway that things are awry.


  15. #15
    Join Date
    Mar 2008
    Location
    Park City, Utah
    Posts
    1,530

    Default Re: Is this OK?

    I went back to look at the radon machine and it is pex on the TPR line. This guy was having a bad day, plus it is a spec home. The PEX is rated for 100 psi at 160 degrees, the plumber said it is acceptable. Any thoughts.


  16. #16
    Join Date
    Mar 2007
    Location
    Dallas, Texas
    Posts
    4,112

    Default Re: Is this OK?

    Watts has a pex looking tpr drain tube made for the purpose. IF it was a purpose built tube from a manufacturer like Watts, I would not have a problem with it. If it is flexible pex, then there is a problem.

    http://www.watts.com/pdf/ES-100DT.pdf

    Jim Luttrall
    www.MrInspector.net
    Dallas, Texas

  17. #17
    Joshua Hardesty's Avatar
    Joshua Hardesty Guest

    Default Re: Is this OK?

    Pex is rated at 100psi at 160 degrees, but the TPR valve blows off at what, 180psi/210 degrees? If it's a straight shot down without making any bends where any pressure could form inside the pipe it probably wouldn't make much difference, BUT it's still not an approved material in the codebooks.


  18. #18
    Join Date
    Mar 2008
    Location
    Park City, Utah
    Posts
    1,530

    Default Re: Is this OK?

    Thanks for all your imput and assistance, you have been very helpful. I am writing it up as further evaluation of the vent. The rest was written up as well. It is a spec home and they cut a lot of corners but it is still a 2 million dollar place, nice work huh.


  19. #19
    Join Date
    Mar 2007
    Location
    Fuquay Varina, NC
    Posts
    1,072

    Default Re: Is this OK?

    I just read this about Pex:


    PEX piping meets all requirements for pressure and temperature performance in residential applications. Consensus standards published by the American Society for Testing and Materials (ASTM) International specify temperature and pressure-resistant capabilities of PEX pipe and all tubing used in residential applications bears the appropriate test marking.
    In the event of a water heating system malfunction, PEX piping is designed to accommodate short-term conditions of 48 hours at 210F (99C) and 150 psi (1034 kPa) until repairs can be made. The most commonly used safety relief valve (T&P) activates (opens) at either of these temperature or pressure conditions. All PEX piping has been tested to withstand T&P activation for 30 days to ensure that safety requirements are met. As such, PEX systems DO NOT require the use of a special T&P valve.

    Mike Schulz License 393
    Affordable Home Inspections
    www.houseinspections.com

  20. #20
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    25,313

    Default Re: Is this OK?

    Mike,

    That is not talking about the use of PEX as the T&P relief valve discharge pipe, that is talking about the PEX piping system being able to withstand those conditions for the stated 30 days.

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

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
  •