DIY Pool Heater - pump sizing questions

[spasticnapjerk]

Hello everyone, my name is Drew and this is my first forum post.

I'm going to build a "redneck pool heater" for my in-ground pool, using a burner from a turkey fryer and about 100 feet of 3/4" copper pipe as the heat exchanger. It's going to be portable and totally independent from the existing pool pump and filter. Plumbing will be really simple - an intake hose, a pump, the copper tubing, and another hose back to the pool.

I think that I'll need a flow rate of somewhere between 700 and 1000 gallons per hour. Any suggestions for pump types? Does anyone know if a cheap ($100 or so) transfer pump would be sufficient?

Thanks for the help!
Drew

 

[speedbump]

Have you done any Engineering on whether the heat your going to add will get ahead of the heat dissipation that is going on with the pool? I don't think a turkey burner will be nearly enough heat for what your trying to do. The other thing to think of is the heat that is lost through copper pipe not above the burner.

As far as the pump goes, as fast as your going to be heating water in 100' of 3/4" copper pipe, a small 12 volt pump like these would be plenty:
http://www.pumpsandtanks.com/Pumps/delavan_pumps.htm

 

[spasticnapjerk]

Thank you for the link speedbump.

I haven't done any engineering but I found a burner that's rated at 210k btu, which should be plenty. It's a small pool and I won't be heating it 24/7, just for day.

The delavan pumps are more expensive than I expected. What do you think about this pump at harbor freight? http://www.harborfreight.com/34-horsepower-clear-water-pump-69297-8705.html

Drew

 

[havasu]

In my honest opinion, anything from Harbor Freight is pure junk, and many items are not UL approved. Caveat Emptor!

(ca·ve·at emp·tor
ˌkavēˌät ˈem(p)ˌtôr/
noun
the principle that the buyer alone is responsible for checking the quality and suitability of goods before a purchase is made.)

 

[speedbump]

I haven't done any engineering but I found a burner that's rated at 210k btu, which should be plenty. It's a small pool and I won't be heating it 24/7, just for day.

The delavan pumps are more expensive than I expected. What do you think about this pump at harbor freight? http://www.harborfreight.com/34-hors...9297-8705.html

Drew

Havasu pretty much summed it up for me on the Harbor Freight items, especially their pumps.
I have to ask, how many degrees do you expect to raise the temp of this pool with this contraption in one day?

 

[havasu]

Speedbump is asking a legitimate question. Using my 250,000 BTU pool heater, it took 2 days of continuous heating to increase the temperature 20 degrees, and cost me about $50. I did it once, years ago!

 

[speedbump]

it took 2 days of continuous heating to increase the temperature 20 degrees, and cost me about $50. I did it once, years ago!

We have customers that run theirs all winter. Can you imagine their heating bills??? And when it gets real cold around December and January, if you don't put a pool cover over it, you can't get ahead of the heat rising off the pool.

 

[havasu]

I guess once you reach your desired temperature, it would be cheaper as days go on because the earth around the pool will get warm. Once I shut off the heater, it became cold overnight and really felt like it was a rip off.

 

[speedbump]

Yeah, I suppose that would happen with the ground around the pool, but it would still be a major expense. At my age, I can't hardly get any of our friends to get into the pool in the summer let alone the winter.

 

[phishfood]

Plus, I am betting that havasu's purpose built pool heater is a lot more efficient at getting those BTU's into the pool water than this system will be.

Sounds like a fun project, though! Definitely worth a case of beer over a weekend.

 

[speedbump]

Sounds like a fun project, though! Definitely worth a case of beer over a weekend.

Count me in!