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Help.....my pool gallonage calculations do not seem right

Help.....my pool gallonage calculations do not seem right

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  #1  
Old 10-02-14, 02:08 PM
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Help.....my pool gallonage calculations do not seem right

Thought I had about a 15,000 gal pool. Service people and contractors have guessed 12,000 to 15,000. It is oblong with more curves than some drawings I have seen on pool forums where you enter LxW and depth at shallow and deep ends. Our is 16 x 32, convoluted oblong shape and is 3 foot deep at both ends and along sides.....and slopes down to the 5 foot deep bottom.

I came up with 12,000 to 15,000 gallons.

PROBLEM IS: Pool was drained dry and I refilled. I tested incoming water. It is 1 gallon in 5 seconds. Went to a 5 gallon bucket. It came out to 25 seconds to fill. This works out to 12 gallons/minute.

I filled from 9am to 9pm, two days ago and shut off water
I filled from 7am to 7pm, yesterday and shut off water.
I filled from 8am today to 12 noon and shut off as water was well into skimmer.

I calculated 28 hours of fill at 12 gpm I keep getting 20,160 gallons. Way more than the various pool calculators tell me.

What is wrong, please ?
 
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  #2  
Old 10-02-14, 02:18 PM
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The gallons per minute is directly proportional to the water pressure. If the pressure changed (as mine does) the 12 GPM you came up with would not be accurate.
If you were on city water you could have used the meter.... if you are on well.... the pressure is all over the place.


My inground pool is roughly 20x40 and is 3' deep in the shallow end and 9' deep in the center of the bowl (deep end). The depth was needed to support a diving board. The calculations are around 22,000 gallons.
 
  #3  
Old 10-02-14, 02:33 PM
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All depends on your water source and supply flow as stated. If a well, flow can change as pump cycles. If city, flow can change as more demand occurs at peak hours.

1st time draining and refilling? If not, is it a big change from last time?
 
  #4  
Old 10-02-14, 03:55 PM
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We are on a well and have a cycle stop valve installed to keep pressure constant. No other water use while filling. This is the first drain and refill.
 
  #5  
Old 10-02-14, 04:55 PM
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In that case...I wouldn't worry about it. Matter of fact, why were you concerned? The old saying "It is what it is" may apply?
 

Last edited by Gunguy45; 10-03-14 at 07:53 AM.
  #6  
Old 10-02-14, 06:47 PM
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Hi Vic....I was curious because there was such a large discrepancy between the amount of water in the pool that went in, last couple of days.....and what others have guesstimated over last 8 years.

I was thinking my math was off
 
  #7  
Old 10-03-14, 05:48 AM
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Math

12 x 60 x 28 = 20,160...............
 
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