How long does it take to heat my pool?

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jamie44
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My Pool: 18x36 inground,hayward 116btu heater,Aqua rite salt generator,Kreepy Krawley,Hayward sand filter
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How long does it take to heat my pool?

Postby jamie44 » Thu 06 Aug, 2009 23:02

I have an 18x36 in ground pool with a hayward 2103 116btu heater. I just put this pool in this week. I am curious as to how long it takes to heat up my pool? How hot should the water be coming out of my heater?


Me...
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How long does it take to heat my pool?

Postby Me... » Fri 07 Aug, 2009 12:25

Generally the water leaving the heater will be about 5 degrees F higher than the water going in. There are 2 internal bypasses that will help that out and these make allowances for many pump sizes and flows. A bigger heater can heat a lot more water to that 5 degree rise than a smaller heater. And of course there are factors such as wind and insulation.

I don't have them at my fingers but I am sure a quick search will find you charts on how many BTUS it takes to heat a pool in a given timeframe. You will have to calculate your heat loss too.

I just took a look at a calculator I built and for an 18x36 25000 gallon pool I ended up with 36-48 hours depending on the various factors. As an aside, I always used about a 250,000 BTU heater on everything, including spas, unless the customer wanted FAST. A bigger heater will also run a lot cleaner and last longer because it wont work itself to death trying to heat the water.
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Pool Clown
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How long does it take to heat my pool?

Postby Pool Clown » Tue 22 Sep, 2009 07:39

Our heater manufacturer (Raypak) has always told us, If the heater is sized for the pool properly, (whole other topic) the heater should be able to heat the pool one to two degrees per hour, not counting heat loss. I agree with Me... that a cover helps control this heat loss. Also, for your notes Jamie, this same configuration should heat the spa 1 to 2 degrees per min.
Factory warranty service for Pentair, Jandy, Raypak, Polaris, and Paramount pool cleaning systems.
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mas985
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How long does it take to heat my pool?

Postby mas985 » Tue 22 Sep, 2009 10:19

It depends on the size of your pool but a 116 BTU heater will raise 10000 gallons of water about 1.4 degrees per hour. 20000 gallons 0.7 degree per hour.
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Pool Clown
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My Pool: Uses a Chlorine generator, not a Salt Water Generator (SWG).
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How long does it take to heat my pool?

Postby Pool Clown » Tue 22 Sep, 2009 18:33

mas985 wrote:It depends on the size of your pool but a 116 BTU heater will raise 10000 gallons of water about 1.4 degrees per hour. 20000 gallons 0.7 degree per hour.

Yes, we rather sell a heater that is over sized (usually) for the pool. That way, we can give this advise, and if it does better, then the customer is that much happier. In my area, customers would rather pay more to have a over sized heater, and have faster heat rise times, than go with the lesser size and have to wait for the temp.

Some manufacturers claim that bigger heaters cost less (gas) to do the job. Some here will strongly disagree with this claim. I have seen the calcs they give, but never been able to verify the price they give for price of a therm of gas. It all depends on the price of gas in your area.

Note to disputers: This is not my claim. your disagreements to this won't be heard by the claimant (probably).
Factory warranty service for Pentair, Jandy, Raypak, Polaris, and Paramount pool cleaning systems.
czechmate
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How long does it take to heat my pool?

Postby czechmate » Sat 26 Sep, 2009 07:25

mas985 wrote:It depends on the size of your pool but a 116 BTU heater will raise 10000 gallons of water about 1.4 degrees per hour. 20000 gallons 0.7 degree per hour.


This may be true in a perfectly controled enviroment as of an indor pool.
There can hardly be calculated input of the outdor element involved, such as current outside temperature, wind direction, etc.
Thing to remember is that your water will not warm up much until it warms up the surrounding gunite.
Simmilar to warm up of soup, that was kept in the fridge in a Corningware pot.
Vinyl in the sand may have different rate of a warm-up.
While you injecticting warmer water into the pool, gunite is absorbing the heat and cold wind is stripping it, as you constantly exposing just warmed up water to the surface.
The tables may give you a general idea of rate of the warm up, but only experience of a particular location combined with the current outside element will tell you, if the picked weekend will be economical to fire up your heater.

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