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Hot water supply calculations.

  1. May 7, 2012 #1
    HI i am a student from Singapore , and i was told to calculate the amount of hot water needed to supply to a house. The design brief stated
    1)Deliver 15 gallons of water at average 110°F (43°C) temperature within 10 minutes; 16 water draws during 1 week
    2)Dishwasher: Successfully wash five loads of dishes during 1 week

    Whats does this specs means? 16 draws means 15 gallons X 16 in a week? also for dishwasher what does it means 5 loads?How do i know how many gallons would it use? Our lecturer had not idea and only asked us look online. I hope you guys could help us. Our rough idea is just solar thermal panels( compulsary thermal instead of PV) , maybe 2-3 panels and a tank. Tank sizing is a porblem too.
  2. jcsd
  3. May 8, 2012 #2
    A "load" refers to the act of loading the dishwasher and then using it. It is the same as "doing a load of laundry"/

    So 5 loads means five uses of the dishwasher.
  4. May 8, 2012 #3
    To "draw water" is a term not used often. Most commonly, people will say "I'm going to draw a bath" meaning they will fill the tub with water.

    So I would say that 16 "water draws" means 16 uses.
  5. May 8, 2012 #4
    Are questions 1 & 2 both refering to a dishwasher?

    Could you post the full question?

    My guess is this:

    1: every "draw" or use is 15 gallons. 16 uses is 16*15 = 240 gallons needed that week.

    2: if the dishwasher uses 15 gallons per use, 10 minutes long... 5 loads will be 5* 15 or 75 gallons.

    I don't think we have enough information from you to answer the questions properly though.
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