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NG pipe sizing

ChrisJ
ChrisJ Member Posts: 12,865
Hi all,

I'm hoping someone can just quickly double check my work here to make sure I'm not being a dope.
These are the sizes I came up with for piping and the incoming line just seems a bit much to me. Am I way off or is this about right?

Supply pressure is 6", although after the meter 5.5" seems more realistic. They give me so much extra to play with..........

Please see the two attached drawings. Hopefully they work.
Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment

Comments

  • Alan (California Radiant) Forbes
    Alan (California Radiant) Forbes Member Posts: 3,261
    edited February 2020
    Yes, a bit too much from what I can tell.

    Table 12-8 in the 2009 Uniform Plumbing Code will allow you to run 1-1/4" schedule 40 pipe and will supply 528 cubic feet a maximum of 60 feet.

    Inlet pressure less than 2 psi, with no more than a 0.5" pressure drop.



    Often wrong, never in doubt.
    ChrisJ
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 12,016
    @ChrisJ
    your good to go. I used low pressure gas chart .05"wc pressure drop
  • ChrisJ
    ChrisJ Member Posts: 12,865

    Yes, a bit too much from what I can tell.

    Table 12-8 in the 2009 Uniform Plumbing Code will allow you to run 1-1/4" schedule 40 pipe and will supply 528 cubic feet a maximum of 60 feet.

    Inlet pressure less than 2 psi, with no more than a 0.5" pressure drop.



    Hi Alan,
    I came up with 80 feet as the longest run when taking fittings into consideration. But I'm also concerned I did it wrong.

    I'd much rather 1 1/4 to be honest.....
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Alan (California Radiant) Forbes
    Alan (California Radiant) Forbes Member Posts: 3,261
    edited February 2020
    At eighty feet, you can deliver 452 cubic feet. Looks pretty good for 1-1/4" pipe, especially with your boiler coming off early.
    Often wrong, never in doubt.
    ChrisJ
  • P.S. Check with your local gas supplier for density. Here, it's 1,000 BTU's per cubic foot.
    Often wrong, never in doubt.
  • ChrisJ
    ChrisJ Member Posts: 12,865

    P.S. Check with your local gas supplier for density. Here, it's 1,000 BTU's per cubic foot.

    I think I had actually asked back in 2011 but I'm not remembering the actual answer. I don't like this getting old stuff....

    Does the btu content effect what appliances actually flow? I assumed they would still flow the same amount and just deliver slightly less or more based on the content?
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • ChrisJ
    ChrisJ Member Posts: 12,865

    @ChrisJ
    your good to go. I used low pressure gas chart .05"wc pressure drop

    Do you think I could get by with an 1 1/4 on the first section, or too close?
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • ratio
    ratio Member Posts: 3,185
    Odds are you won't notice the difference going with 1¼". something like 70-80% of the gas lines I come across in the wild are undersized according to the old tables, but only like 10-20% of the equipment gives me trouble. :wink:

    Can you get the 1½" cut & threaded at a big box store? If they get the dies in the right order, they'll usually pull up tight enough.

    ChrisJ
  • ChrisJ
    ChrisJ Member Posts: 12,865
    > @ratio said:
    > Odds are you won't notice the difference going with 1¼". something like 70-80% of the gas lines I come across in the wild are undersized according to the old tables, but only like 10-20% of the equipment gives me trouble. :wink:
    >
    > Can you get the 1½" cut & threaded at a big box store? If they get the dies in the right order, they'll usually pull up tight enough.

    I'll be using my 65R-TC
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 12,016
    @ChrisJ

    Yes, 1 1/4 is fine for the first section.
    ChrisJ