Coal fired pool heater

Re: Coal fired pool heater

PostBy: EarthWindandFire On: Mon Aug 22, 2011 3:00 pm

I noticed a few weeks ago that DS makes a bucket-a-day coal stove.

Could this be used to heat DHW or a pool?

For pool heating a circulator would be required right?
Last edited by Richard S. on Fri Dec 13, 2013 7:26 am, edited 1 time in total.
Reason: <removed dead link>
Hot Air Coal Stoker Furnace: Leisure Line Lil' Heater.
Hand Fed Coal Stove: Hitzer model 75.
Other Heating: Oil and Natural Gas.

Re: Coal fired pool heater

PostBy: ValterBorges On: Sat Sep 24, 2011 8:44 pm

Related questions?

1. Would it be ok to hook up the heat exchanger after the return from a propane heater.
My thoughts were to open up next year with the 400k/btu propane heater and heat exchanger simultaneously and once up to temp shut off the propain$$$$, just have the heat exchanger running. ... key=10003P

cupro-nickel for use in SWG pools ... scupro.htm


2. What do you guys use to regulate the temp going to the heat exchanger zone? aquastat? not necessary?
I typically run my pump 4 hours a night would I need to run more frequently? or is this going to be enough to
maintain temp with the 200k btu heat exchanger.
I would like the water between 80F, much hotter is not desirable.
Sometimes I get a 10-15 degree drop overnight plan on getting a solar cover next year to counter act a bit.

18,000Gal pool w/ 1.8 HP pump using the BBB method from works great for me.
S260 Boiler, 200ft run to pool
Stove/Furnace Make: AHS
Stove/Furnace Model: S260

Re: Coal fired pool heater

PostBy: btrowe1 On: Sat Oct 01, 2011 6:22 pm

This has to be one of the best explainations on Boiler sizing I have read in a while,, :idea:

EarthWindandFire wrote:I am posting this for future reference:

The goal is to have a heater that has enough capacity to heat the pool to your desired level in a reasonable amount of time. Maintaining that temperature is a lot easier once the pool is up to temp.

First, the capacity of most pool heaters are rated in BTU's or British Thermal Units. One BTU is the amount of heat required to raise the temperature of one pound of water, one degree F. And since there are 8.33 gallons of water per pound, it takes 8.33 BTU's to raise one gallon of water, one degree F.

Now let's calculate:

1. Determine the number of gallons in your pool (G).

2. Determine the amount in temperature that you want to raise the pool temp (the easiest way to figure this is to use the air temp as the minimum and the desired pool temp as the maximum) (Delta T).

3. Calculate the number of BTU's needed (BTU) per gallon of water by multiplying step 2 x 8.33. Multiply this number times the gallons of water in your pool (G). This is the number of BTU's to raise your pool temp from the minimum to desired temp.

4. Determine how FAST you want to be able to go from the minimum temp to the desired temp (in hours) (H).

5. Divide the total number of BTU's from step 3 by the hours in step 4 to yield the BTU'S per hour that your heater will need to deliver.

6. Multiply Step 5 by a error factor of 20% and add to step 5. This is approximately the size of heater that you will need.


1. Assume pool volume, G = 10,000 gallons 2. Assume 80F desired pool temp and 60F air temp. Delta T = 80 - 60 = 20F 3. BTU's per gallon x Delta T: 8.33 x 20 = 166.6 BTU's per gallon. BTU/Gal x Gallons (G): 166.6 x 10,000 gal = 1,666,000 Total BTU's. (Wow, seems like a lot!) 4. Assume I want to be able to warm the pool in two days of continuous operation = 48 hours. 5. Total BTUs / Hours: 1,666,000 / 48 = 34,708 BTU's per hour. 6. (BTU/Hr x 20%) + BTU/Hr: 34,708 x 0.20 = 6,941 BTU's 6,941 + 34,708 = 41,649 BTU's per hour.

Now, most pool heaters come in a round number of BTU's like 50,000, 100,000, 150,000, etc. You should select the closest size to your needs (usually on the higher side is best).

Hence, for this example, a 50,000 BTU heater would be more than adequate.

Obviously, you could also work these calculations backward to determine what Delta T you could handle given a certain size heater and pool size.
Hot Air Coal Stoker Furnace: Alaska stoker 140 Coal
Stove/Furnace Make: alaska stove