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    #46
    Originally posted by david luchini View Post
    Your math is wrong. Both of these solutions equal 47.275.
    The equation using 440.33 with the resultant figure (46.15) is correct in terms of the given numbers presented in the equation.

    However, OP (either a typo) or misreading the article (430.24.) had written the multiplier 0.25 instead of 1.25.

    The math is correct, the way it was presented in terms of how the article should be presented is different. (0.25 vs 1.25) .
    I would be glad to hear from OP regarding this.

    This borders on pedantry. . . and you know better than that.



    Comment


      #47
      Originally posted by myspark View Post

      The equation using 440.33 with the resultant figure (46.15) is correct in terms of the given numbers presented in the equation.
      No, it's not.

      Originally posted by myspark View Post
      However, OP (either a typo) or misreading the article (430.24.) had written the multiplier 0.25 instead of 1.25.
      Replacing the 1.25 with 0.25 in the 430.24 solution would give a drastically wrong answer.

      Originally posted by myspark View Post
      B]The math is correct, the way it was presented in terms of how the article should be presented is different. (0.25 vs 1.25) .[/B]
      I would be glad to hear from OP regarding this.
      The math is wrong...the way it is presented in terms of how the article is presented IS different.

      I'd be glad to hear from the OP as well. His point seemed to be that using two different methods would produce "almost the same answer."
      In fact, he presented the same equation in two different manners and somehow came up with different answer each time. Neither of which answer is correct.


      Comment


        #48
        Originally posted by david luchini View Post

        No, it's not.



        Replacing the 1.25 with 0.25 in the 430.24 solution would give a drastically wrong answer.



        The math is wrong...the way it is presented in terms of how the article is presented IS different.

        I'd be glad to hear from the OP as well. His point seemed to be that using two different methods would produce "almost the same answer."
        In fact, he presented the same equation in two different manners and somehow came up with different answer each time. Neither of which answer is correct.

        It was a misplaced cells in excel in placing the formula. Thank you for the correction, both of them are 47.275.

        Comment


          #49
          Originally posted by david luchini View Post

          No, it's not.



          Replacing the 1.25 with 0.25 in the 430.24 solution would give a drastically wrong answer.



          The math is wrong...the way it is presented in terms of how the article is presented IS different.

          I'd be glad to hear from the OP as well. His point seemed to be that using two different methods would produce "almost the same answer."
          In fact, he presented the same equation in two different manners and somehow came up with different answer each time. Neither of which answer is correct.

          You are just parroting what I already said.
          The math is correct. . . the "ipso facto" details that OP used does not match with the NEC guidelines.

          I am eager to hear from OP. . . and there is no need for resorting to punitive insinuations.



          Comment


            #50
            Originally posted by myspark View Post

            You are just parroting what I already said.
            I haven't parroted what you have said...I've disagreed with you.

            Originally posted by myspark View Post

            The math is correct. . . the "ipso facto" details that OP used does not match with the NEC guidelines.
            I'm still disagreeing with you...as the math was not correct. Fortunately, the OP has discovered his error. Also, statements of fact are not "punitive insinuations."

            Comment


              #51
              The way I interpret 440.33 is below

              1. Sum of all RLA (or branch circuit selection whichever is greater) of all motor compressors
              2. Sum of FLC of all other motors (indoor & out door)
              3. and 25 % of highest motor compressor or FLC in the group

              Item 1 = need to add all RLA of all motor compressors involved
              Item 2 = need to add all FLC fan motors involved
              Item 3 = says 25% of highest RLA or FLC. (It didn't say 125% of the highest)

              If my interpretation is correct then the collective discussion from JJ & David seems to be on the same page. (Based on a typical PACU nameplate data I got)

              Comment


                #52
                Originally posted by myspark View Post


                However, OP (either a typo) or misreading the article (430.24.) had written the multiplier 0.25 instead of 1.25.

                The math is correct, the way it was presented in terms of how the article should be presented is different. (0.25 vs 1.25) .
                I would be glad to hear from OP regarding this.



                Comp 1 = 12.20
                Comp 2 = 16.70
                OFM 1 FLA = 3.90
                OFM 2 FLA = 3.90
                IFM FLA = 6.40

                Solution 1, using 440.33
                = (16.7 x 0.25) + 12.20 +16.70 + 3.90 +3.90 + 6.40
                = 47.275

                Solution 2, using 430.24
                =(16.7 x 1.25) + 12.20 + 3.90 + 3.90 + 6.40
                =47.275

                I didn't use 0.25 multiplier in 430.24.

                Comment


                  #53
                  Originally posted by david luchini View Post

                  I haven't parroted what you have said...I've disagreed with you.


                  I'm still disagreeing with you...as the math was not correct. Fortunately, the OP has discovered his error. Also, statements of fact are not "punitive insinuations."
                  OP hasn't responded and for you to make that harsh assessment (that he is wrong) is just another one of your hypocritical remarks . . . as always.
                  You can disagree with me come hell and high water. . . but it doesn't mean your statement is valid.

                  Comment


                    #54
                    Originally posted by Thomas&Kulas View Post


                    Comp 1 = 12.20
                    Comp 2 = 16.70
                    OFM 1 FLA = 3.90
                    OFM 2 FLA = 3.90
                    IFM FLA = 6.40

                    Solution 1, using 440.33
                    = (16.7 x 0.25) + 12.20 +16.70 + 3.90 +3.90 + 6.40
                    = 47.275

                    Solution 2, using 430.24
                    =(16.7 x 1.25) + 12.20 + 3.90 + 3.90 + 6.40
                    =47.275

                    I didn't use 0.25 multiplier in 430.24.
                    No, you didn't use 0.25 multiplier in 430,24. You used it in 440.33.
                    Read your first equation.

                    Mabuhay!

                    Comment


                      #55
                      Originally posted by myspark View Post
                      You can disagree with me come hell and high water. . . but it doesn't mean your statement is valid.
                      I'm sorry that you have problems with facts. Surely you are in jest when you suggest that statements of fact are "hypocritical remarks."


                      I'm afraid I will have to disagree with again. You said this in post #53...

                      Originally posted by myspark View Post

                      OP hasn't responded and for you to make that harsh assessment (that he is wrong)
                      The OP said this in post #48...

                      Originally posted by Thomas&Kulas View Post

                      It was a misplaced cells in excel in placing the formula. Thank you for the correction, both of them are 47.275.
                      The fact is, the OP responded and admitted that he was wrong. I'm not really sure why you feel the need to argue this.

                      (16.7 x 0.25) + 12.20 +16.70 + 3.90 +3.90 + 6.40 is fairly simple arithmetic...I would say it is indisputable that that expression does not reduce to 46.15.

                      Comment


                        #56
                        Originally posted by Thomas&Kulas View Post

                        If my interpretation is correct then the collective discussion from JJ & David seems to be on the same page. (Based on a typical PACU nameplate data I got)
                        I think you've misunderstood what JJS was arguing. He was concerned with FEEDER sizing, not with Branch Circuit sizing.

                        Comment


                          #57
                          Context is important. Multiplying a number by 1.25 is the same as adding .25 of the number to itself.

                          Sent from my XT1585 using Tapatalk

                          Comment


                            #58
                            Originally posted by GoldDigger View Post
                            Context is important. Multiplying a number by 1.25 is the same as adding .25 of the number to itself.

                            Sent from my XT1585 using Tapatalk
                            Or, the argument can go on and people are talking the same thing!

                            Comment


                              #59
                              Originally posted by Thomas&Kulas View Post


                              I'm a newbie but seems both of you JJS & David are correct. Where ever you loop it will come up with almost the same answer.

                              440.35 will direct you to 440.4(B) which will direct you to 440.34 which will then direct you to 440.33 that says (Highest RLA x 0.25) + all RLA & FLA

                              while 430.24 says (Highest FLA x 1.25) + all FLA in the group.

                              I.E
                              Comp 1 = 12.20
                              Comp 2 = 16.70
                              OFM 1 FLA = 3.90
                              OFM 2 FLA = 3.90
                              IFM FLA = 6.40

                              Solution 1, using 440.33
                              = (16.7 x 0.25) + 12.20 +16.70 + 3.90 +3.90 + 6.40
                              = 46.15

                              Solution 2, using 430.24
                              =(16.7 x 1.25) + 12.20 + 3.90 + 3.90 + 6.40
                              =47.15

                              This is a typical PACU which compressors are designed either with the same rating (RLA) to balance the loading conditions or with just a minimal difference such in given example.


                              Same thing was calculated in both those examples.

                              First one has 16.7 x 0.25, then later adds 16.7
                              Second one has 16.7 x 1.25
                              The rest of the each example are identical

                              (16.7 x .25) + 16.7 gives you same result as 16.7 x 1.25.

                              For some reason he had a math error in both examples as the answer to both should have been 47.275.
                              I live for today, I'm just a day behind.

                              Comment

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