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Recent content by sspeare

  1. sspeare

    Geothermal piping calculations

    Anti-freeze? I have a link below, on Dow-Frost GEO 20. You can get the thermal properties of GEO-20 anti-freeze/water mix from the brochure in the link. Don't use standard automotive anti-freeze, use an anti-freeze formulated for "geo" and/or HVAC applications. Read Dow's literature to...
  2. sspeare

    Geothermal piping calculations

    In my most recent post, I failed to note a link included to a PDF that contains, among other things, an explanation of "Heat of Rejection."
  3. sspeare

    Geothermal piping calculations

    To answer prichmon's question: what is the Heat of Rejection? Suppose you calculate the Total Cooling Load (sensible + latent) of an office space at 10 Tons. You might think that you only have to size the "heat sink" (whether a cooling tower or an array of boreholes) to accept 10 Tons. But...
  4. sspeare

    Geothermal piping calculations

    prichmon, you probably should have posted this to the HVAC/R forum. Anyway, be wary of rejecting heat into the ground 24/7. If you have ZERO heating load, you'll never have to extract any heat from the ground. When you reject heat 24/7 into the ground, the "borehole field" gets "saturated."...
  5. sspeare

    Geothermal piping calculations

    OK, here are some thoughts: I assume your 273,000 BTUH includes all the Heat of Rejection from the refrigeration equipment. Tons = 273,000 BTUH) / (12,000 BTUH/Ton) = 23 Tons to be rejected to the ground. Borehole Depth: I use a 180 foot deep vertical borehole to reject each Ton. By "Ton"...
  6. sspeare

    Geothermal piping calculations

    The original post says: 35*F differential equates to 1,315 feet of copper pipe, at "total power usage" of 80 KW. My question: what BTU per hour are you trying to reject into the ground? Is it (80 KW x 3413) = 273,040 BTU/hour?
  7. sspeare

    Boiler Room Emergency shutoff

    In my State, Pennsylvania, boiler installations must comply with ASME Standard CSD-1-2004, which is titled: "Controls & Safety Devices for Automatically Fired Boilers." Paragraph CE-100(a), in ASME CSD-1-2004, says it this way: "A manually operated remote shutdown switch ...... shall be...
  8. sspeare

    Insulation calculation to prevent condensation

    ivoryhorseman: possible typo in your post? If the radius is 20 cm, then diameter = 40 cm, or 15.7 inches. But you said the wall thickness was 50 cm (= 19.6 inches ?) I'm lost. Anyway, just to get you "in the ballpark", you might try a few possibilities out at the attached site. Also, as...
  9. sspeare

    elevated water supply to pump

    You say this is your first water system design. You should get the book "Cameron Hydraulic Data." The first chapter is an excellent treatment of pump inlet/outlet conditions, lift, suction lift, NPSHA, etc. The book is essential for anybody who designs piping and selects pumps. Good luck...
  10. sspeare

    Elevator Shaft Smoke Detectors

    Guys, on 3 July I posted 2 pages from the ASME Elevator Code.
  11. sspeare

    Elevator Shaft Smoke Detectors

    A smoke detector is required in the hoistway, IF there is a sprinkler head in the hoistway. BUT, per the 2007 edition of NFPA 13, you can OMIT the hoistway sprinkler under certain conditions. Paragraph 8.15.5.5 of the 2007 edition of NFPA 13 tells you how to omit the hoistway sprinkler. I...
  12. sspeare

    Elevator Shaft Smoke Detectors

    I attached 2 pages from the second Addenda to ASME A17.1b-2003, relating to smoke detectors in the hoistway.http://files.engineering.com/getfile.aspx?folder=136d42dc-e6e4-445a-bb0a-67e829e2401f&file=Elevator_Smokes_per_ASME_A17-1b-2003.pdf
  13. sspeare

    Elevator Shaft Smoke Detectors

    I will quote from a very "old" (2002 edition) NFPA 72 National Fire Alarm Code: Chapter 6 Protected Premises Fire Alarm Systems. 6.15.3 Elevator Recall for Fire Fighter's Service. 6.15.3.6 Smoke Detectors shall not be installed in un-sprinklered elevator hoistways unless they are installed...
  14. sspeare

    Fault current calculations

    You should do this work under the direction of an experienced Engineer. Nobody can simply give the "know-how" to you. You have to study. I suggest reading the Bussmann publications on fault calculations. See the link...
  15. sspeare

    Need Manufacturer recommendation

    You might try AAON. I can't guarantee they have horizontal discharge & 480 Volt. But I can tell you that AAON does offer just about any configuration & option you can imagine. Here is a link:http://www.aaon.com/product.aspx?id=1

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