Wood Burning Heaters

[cruzr]

Hi all, Im a new member, and interested in purchasing a wood fired heater. I would appreciate anyones input that owns or has any experience with them. My wife and I live in a rural area and heat our home with wood. I also have a propane furnace for back up. I have already done a search here, and found a 2009 thread on "Extend a Swim" heaters. I would like to hear your thoughts if your still here. We had an IG shotcrete 18x36 dug and poured, and currently waiting for warm weather to plaster pool. We would appreciate any thoughts or comments.

[Pool-newb]

Hi all, Im a new member, and interested in purchasing a wood fired heater. I would appreciate anyones input that owns or has any experience with them. My wife and I live in a rural area and heat our home with wood. I also have a propane furnace for back up. I have already done a search here, and found a 2009 thread on "Extend a Swim" heaters. I would like to hear your thoughts if your still here. We had an IG shotcrete 18x36 dug and poured, and currently waiting for warm weather to plaster pool. We would appreciate any thoughts or comments.

That was probably my post that you read and while I don't post much here, I do monitor from time to time. I guess this is a good time to update my experience.

I've had it for a few years now and I now better understand the laws of physics. The point is that it takes a huge amount of energy to move that much water from cold to warm despite mine being a small pool, and so, in the Atlanta area, the word "Extenda-Swim" really is appropriate. Since my pool is in a lot of shade, about all I can do with the heater is extend the season - open early and close late.

Some of the finer points I've learned:

- This particular brand of heater is not very efficient. While it is well insulated, I think a huge percentage of the actual heat goes up the chimney. If I had enough time and energy I would make some design changes to this one that involved a small fan of some kind blowing air in to the fire box through a lot of well distributed small holes, and then routing the gases in a zigzag around all of the heat exchanger using some steel plating in between the heat exchanger layers. I would also set it up so I could open the fire box and clean the pipes without having to reseal it with caulk each time.

- I ordered the middle sized heater for a small (7800 gallon) pool and that was certainly not overkill. I'd guess it takes about a day to get a 10 to 15°F rise, depending on wood.

- Cover the pool when you're heating but not swimming. I have two solar covers on it on cool days, and I'm not going to do much off-season heating until I can build some kind of building around the pool making it "semi-indoor". Heat lost to the ambient air is huge and fast.

- Type of wood will make a large difference in how fast the temp rises and how often you need to add. Since you heat your home with wood I'm hoping you know more than I do about the BTUs contained in different types of wood, but of the several large trees worth of wood I have, I've noticed that a white wood (I think it's white oak) burns a lot hotter. So I tend to try to put several smaller pieces of white wood to get things started, then one or two pieces of white wood with large chunks of the slower stuff for the long burn.

- I don't recommend doing this if you don't have a cheap to free source of wood. If you have to pay someone to cut, season, haul and stack, you'd probably be better off paying the $500/month to I've heard it costs to run a gas heater.

- They do generate smoke so doing this in a suburb subdivision is not as smart as in the woods. I've learned how to keep the smoke to a minimum, and I am also constantly asking my very nice neighbors if they are having any problems. They have been banned in some suburban areas.

Sooo....

• - Do you have the facilities and desire to work with steel to improve the design a bit?
• - Do you really enjoy hauling, stacking, cutting, etc wood?
• - Do you have a cheap to free source of fire wood?
• - Is your pool indoors or will you keep it well thermal covered when not in use?
• - Are you in the boonies where wood smoke won't make the mall shoppers cough?

The more emphatic yeses you answer, the better the fit.

Hope this helps, let us know what you decide!

[cruzr]

Thank you Pool-newb for the update, yes it was your thread that is very informative. I have been seaching pool forums for a few months now, and just havent found any user info. until finding your posts. Thanks for taking the time to give such an extensive amount of info. It has answered so many of my questions. I have a fireplace insert that was manufactured in the 1970,s but is no longer made. It heats my entire 2400 sq.ft. home. I burn seasoned white and red oak. Although we live on 10 acres with almost all oak trees, I buy most of my firewood. It is still much less than using propane and is a much warmer heat. I think some of your theories/suggestions are right on target. I would like to hear from some one using the Canadian heater if any users are out there. Again any input would be appreciated.

[cruzr]

Since no users of the Canadian wood heater, seem to be on any pool forums. I have decided to purchase the XLarge Extend A Swim heater. Most of my answers are "yes" to Pool-newbs questions. I will say that all my emails were replied to promptly and with details to all of my questions. I will give a report to the forum, of my experiences with Extend A Swim after some use.