Heating above ground pool options.

[blewbyu]

This is a first for me so please be patient. I have lurked for a year or so and haven't really had any challenges with our above ground pool until this year. We haven't been able to use it much this season due to weather and lack of warmth. We can't get the temperature above 80 degrees. We currently use 2 2x20 solar heaters, could use another panel but this year it wouldn't have mattered. We lacked sun to produce heat. Always keep it covered and run the pump when there is sun. No luck. We are two adults who like it warm. We are considering an outdoor furnace/wood heat. Is anyone out there using this set up? We are going to do some shopping this fall for a furnace but sales people in general will tell you what you want to hear, I need to know if it will actually work. We have the wood and the space for the furnace, in the future we are planning a greenhouse as well. I figure the outdoor furnace can heat the pool and when needed the greenhouse as well.
Any thoughts or suggestions are appreciated.

 

[dmanb2b]

Hi Bleu...welcome to TFP.

I think you most cost effective solution would be to add 1 or 2 more 4x20 panels. We had one 4x20 solar bear panel on a 24ft round this summer in NY, the weather has dismal at best...very few days at 90 deg outside temp, yet our pool water has consistently been at 78-86 deg. I get sun exposure on my single panel from 9am-3pm, which is when I run my pump and the solar cover goes on every night. Now we also have a pretty dark liner, so what I've found is that the liner itself helps a lot by keeping the solar cover off during the day and let the sun do it's job bottoms up. If you keep the solar cover on during the day, it actually doesn;t do that much warming, rather it is a better insulator.

Hope that makes sense...good luck in your quest for warmer water

 

[duraleigh]

I attempted what you are considering. Be prepared to use a tractor trailer load of wood.....I'm serious.

When you calculate the number of btu's required to heat your pool vs. the output of your wood stove, you will be astounded. That wood stove will do a great job heating the green house but the btu requirements for a pool are massive.

 

[blewbyu]

Thank you for the response. May I ask what kind of wood burner you planned to use. Here in Southeast Wisconsin many homeowners use the outdoor wood furnace to heat their homes, I would have thought the number of BTU's wouldn't have been an issue. We are researching and actually trying to locate homeowner's that we can talk to using this set up. Wood isn't an issue, we are presently clearing 1/2 an acre of trees. Don't have indoor fireplace yet so thought this would be an ideal situation. We are not quite prepared to use the furnace to heat the house, it is something that perhaps we would consider in the future.

 

[duraleigh]

I heat my house (4000 feet) with my wood stove here in the milder climate of NC. The stove has a capacity of 150,000 btu which is large enough but barely.

If you were to attempt to heat your pool, I would guess you would need about a 300,000 btu woodstove (at least) and the amount of wood you would burn would be, again, stunning.

You need an engineer to do the btu calcs for you and, of course it depends on how hot for how long you want to heat the pool but don't underestimate the energy it takes to heat water compared to heating air.

If you go for it, I have a really nice water-to-water heat exchanger I woulod like to sell. :lol:

 

[matt4x4]

I'm sure your neighbour's won't mind the noise:
http://www.youtube.com/watch?v=Jd5Ze_hq ... re=related

The cheapest way is to harness the power of the sun - solar panels.

 

[NWMNMom]

Solar has always been the most effective and efficient way to heat for us except the last two summers which lacked sun exposure and had such COLD nighttime temps. The panels got the water up to 80-82 days with sun and the 39-45 degree nights, in July with a slar blanket cover on, would drop it down to mid-upper 70s too cold for me. I wonder if insulating the outside walls of the pool or supplementing the panels with another source on those cloudy days is a better option? So it isn't about heating many degrees but just 4-5 additional degrees, the difference between wishing and swimming.

 

[blewbyu]

We actually looked into the gas heater option and have since decided to stay with the solar panels. We currently have 2 - 2x20 panels which worked well up until last season, similiar to yours. This year we are adding 2 more 2x20 panels and upgrading the solar cover to the clear one. The drawback to the solar is the amount of space required, we have 2 acres but the area where the pool is close to the house, deck and garden. We built beds for the garden, laid down fabric and have decided to widen the garden area to accomodate the mats. We will lay fabric and mulch so it all looks like it belongs in the garden area. No more dead grass under the mats. The garden gets 10 hours of sun so the mats will do better, we are also going to get a timer to run the pump longer each day. We've never really had to run the pump daily which may have been a mistake. We are two full time working adults so our pool time is limited to weekends and our day off during the week. We are hoping this will allow us time in the evenings to jump in as well.
Thank you for the response, farmers almanac is calling for hot in July, don't know about August yet but we'll keep our fingers crossed.

 

[bk406]

To try and answer the OPs question. It takes 1 BTU to raise 1 pound of water 1 degree. Looks like he has a ~20,000 gallon pool. A 20 degree rise in temp would take roughly 3.3 million BTU. With a 100,000 BTU wood stove, it would take 33 hours of continuous 100,000 BTU output to raise the 20 degrees. How much wood that would take i have no clue.

 

[duraleigh]

Based on what I burn, I would speculate somewhere around a full chord of wood to output a 100k btu for 33 hours. There's certainly much more btu's in the wood but woodstoves are infamously inefficient. This is only a guesstimate based on my experience.

How about btu's to maintain.....perhaps too many factors to be accurate?

 

[bk406]

How about btu's to maintain.....perhaps too many factors to be accurate?

Yea, thats a toughy. Lots of variables. Exposure to wind, night time temps, use of a solar cover, etc.

During heating season, (May-mid June, mid August -Setember) i lose 5-7 degrees overnight. Thats rough since sometimes I lose more or less depending on the low temp. A 5 degree overnight loss would be about an 8 hour run time.

I dont think a wood stove is feasible to heat a pool. Nobody asked my opinion, but those attic heaters that people talk about are not feasible either, IMO.

 

[Ohm_Boy]

Here's how the big boys get their burnin' wood... they have a line of trucks bringing in chips and they unload 'em fast.