Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Commercial Boiler pressure

LPGasman
LPGasman Member Posts: 18
in THE MAIN WALL
Can anyone help me find the code for operating pressures on a commercial HW boiler for New York State? We had an Weil McLain boiler firing at 1.75 g.p,h fail inspection because the inspector said the pressure shouldn't be 22 p.s.i. I'm not sure if the guy is mistaken or this is legit.

Comments

  • SWEI
    SWEI Member Posts: 7,356
    What rating is on the PRV, and what is the max scale on the pressure gauge?
  • LPGasman
    LPGasman Member Posts: 18
    PRV is 30 psi


  • deadmansghost
    deadmansghost Member Posts: 32
    The boiler rating plate should show the maximum operating pressure.
  • SWEI
    SWEI Member Posts: 7,356
    I'm not aware of a hot water boiler rated at less than 30 PSI. We run several at 27 PSI in tall buildings with no issues.
  • Matt_67
    Matt_67 Member Posts: 301
    Did he think it was a steam boiler?
    LPGasman
  • Paul S_3
    Paul S_3 Member Posts: 1,280
    inspector was probably wrong ...I hear stories all the time in nyc of 2 different inspectors saying 2 different things.....
    ASM Mechanical Company
    Located in Staten Island NY
    Servicing all 5 boroughs of NYC.
    347-692-4777
    ASMMECHANICALCORP@GMAIL.COM
    ASMHVACNYC.COM
    https://heatinghelp.com/find-a-contractor/detail/asm-mechanical-company
  • LPGasman
    LPGasman Member Posts: 18
    I called the Inspector and asked for the "code" he was using as his basis for tagging the unit. Still waiting for his call, probably not going to happen.
  • Paul S_3
    Paul S_3 Member Posts: 1,280
    do you have a copy of the boiler code in your area? if not have it handy
    ASM Mechanical Company
    Located in Staten Island NY
    Servicing all 5 boroughs of NYC.
    347-692-4777
    ASMMECHANICALCORP@GMAIL.COM
    ASMHVACNYC.COM
    https://heatinghelp.com/find-a-contractor/detail/asm-mechanical-company
  • SWEI
    SWEI Member Posts: 7,356
    edited March 2016
    How tall is the building? Multiply the height in feet from the boiler to the highest point in the piping by 0.434 and add ~5 PSI. That's the static pressure you need to keep air out of the system. It's also one reason you sometimes find boilers installed on the top floor.
  • BobC
    BobC Member Posts: 5,502
    The Great and Powerful OZ does not look kindly on those who question his wisdom.

    Bob
    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • SWEI
    SWEI Member Posts: 7,356
    Sometimes you have to call OZ's boss -- or his boss's boss' boss.
  • gennady
    gennady Member Posts: 839
    Pressure relief valve shall be set at maximum rating of the boiler.
    Gennady Tsakh
    Absolute Mechanical Co. Inc.
  • SWEI
    SWEI Member Posts: 7,356
    What about all those CI boilers that are rated for 50 or 75 PSI but ship with a 30 PSI relief valve?
  • gennady
    gennady Member Posts: 839
    SWEI said:

    What about all those CI boilers that are rated for 50 or 75 PSI but ship with a 30 PSI relief valve?

    You specify working and maximum pressure on application for boiler installation permit. Then you order boiler with valve according filing documents.
    Gennady Tsakh
    Absolute Mechanical Co. Inc.
  • SWEI
    SWEI Member Posts: 7,356
    That makes at least some sense ;)

    Still haven't heard a valid reason why a hot water boiler is not permitted to operate at 22 PSI.
  • gennady
    gennady Member Posts: 839
    edited March 2016
    SWEI said:

    That makes at least some sense ;)

    Still haven't heard a valid reason why a hot water boiler is not permitted to operate at 22 PSI.

    Maximum pressure is 1.25 of operating pressure. 22 PSI operating pressure should be OK for 30 PSI safety valve.
    I go through this with every boiler installation
    Why not 22 is because installer has to prove his point to inspector. When inspector asks question, installer should explain and prove his point.
    Gennady Tsakh
    Absolute Mechanical Co. Inc.
  • SWEI
    SWEI Member Posts: 7,356
    Of course, as do we.

    39 feet of system height would do it.

Categories