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I am researching the capability of a 40-gallon electric hot water tank

durazo | Posted in General Questions on

If water is tested at 2 AM and it takes 3 mins to reach 143 degrees (no one used any water for the previous 9 hours) temperature outside is 62 degrees and someone used the water at 2 pm (washer, dishwasher being used) temperature outside is 89 degrees, would it still take 3 mins to reach 143 degrees?

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  1. GBA Editor
    Martin Holladay | | #1

    You haven't provided us enough information to answer your question.

    You told us that the water heater "takes 3 minutes to reach 143 degrees." But you didn't answer a basic question: What were the conditions at the start of the 3-minute time frame under discussion? In other words, what was the starting water temperature?

    In the second example, you propose that "someone used the water at 2:00 p.m.," but you didn't tell us (a) how many gallons of hot water were used, nor (b) the temperature of the incoming water.

    I'm not sure what you are trying to determine.

  2. NormanWB | | #2
  3. Expert Member
    Dana Dorsett | | #3

    The answer is clearly "yes", in some sets of conditions.

    The answer is clearly "no", in some other sets of conditions.

    So if I had to guess, I'd give it a definite "maybe!"

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