Heat Exchangers

[Dan Blatt]

Does anyone have any suggestions as to make of heat exchanger one should consider for purchase? In the process of setting up a natural gas heating system on my pond. Several stainless steel exchangers out there that I've seen - Kerin's site, East Riding Koi site, and others but outside of btu output not much info on dimensions etc. Are they all similar or do any stand out as far as being more efficient? I'm assuming several members here have them on their ponds. Any advice would be greatly appreciated.

[Bob Winkler]

I have had two 350,000 BTU Heat exchangers made by Keeton in Fort Collins on my pond for years. (These are the people who developed Lymnozyme) They worked beautifully. No scientific data, but would do the same ones again, if I was building a pond again. www.keetonaqua.com

Hope that helped.

Best regards,

Bob Winkler

[Motown]

How many BTU/hr are you looking at? How much space do you have for th exchanger?

[Dan Blatt]

Thanks Bob - I'll check that out.
Motown - not sure as of yet. Pond is 4500 gallons - 17 x 6 x 6.6 (average depth) - 7ft. 2 inches deep at the two bottom drains with air domes. I have insulated the walls with 2 1/2 inches of foamcore - 60 % of the pond is below ground and the remainder above but protected by deck and walls. The pond temperature this winter (Olympia, Washington) only dropped slightly over 2 degrees F in a 24 hour period during the worst weather we had - snow and ice. Generally only moves up or down about 1 degree F in a 24 hour period - even going into spring like weather. I have rigid covers with clear polycarbonate on the pond during late fall and winter (still on at the moment). Putting in a gas tankless water heating system for the heat source feeding a stainless heat exchanger - still figuring out exactly what I need and if I should go slightly bigger as far as the components are concerned. Suggestions (size,btu's)welcome.

[Ruth Rice]

hi Dan,
Do you have a picture of your pond that you could post? I was wondering what kind of construction it is with some of it being out of the ground.
Ruth

[Dan Blatt]

Ruth - here's a couple. You really can't see the portion above ground as it is covered by deck. From deck level to ground is approximately 3 ft. The remaining 4 ft. is in the ground. Basically you have a 3 ft. crawlspace under the deck in the picture. Hope that helps.

[Dan Blatt]

Ruth - With covers on during the winter.

[Ruth Rice]

Hi Dan,
Thanks for posting the pictures. I always like to see people's ponds. Is it block construction or made out of wood? I was wondering about the part out of the ground.
Also about the cover, it looks like it is made out of those panels (that are hard to find around here- poly carbonate I think?). Most of them I've seen are only 4 ft long. Is there a frame in the center that they butt up to or are they longer panels?
I like your red fence.
Ruth

[Mike Mazur]

http://www.aquaticeco.com/index.cfm/...ories/ssid/380


never enough sources for info here are a few more to look at.

[Dan Blatt]

Ruth - sorry I didn't see your reply and questions until now. The whole construction is 2 x 6 treated walls on 1 foot centers with 1/2 inch treated plywood on both sides.. Individual wall sections - 8 of them - approximately 6 foot wide by 8 foot tall (2 on the ends and 3 on each side) are bolted to 6 x6 treated corner posts an 4 x6 treated posts down the sides sunk and cemented 2- 3 feet in ground below the bottom of pond. About 60 % of the walls are below ground level. The above ground portions are also tied into the deck frame structure for additional support. All walls have 2 inch foamcore insulation in them with 1/2 foamcore insulation on the inside plywood walls for the pre-formed liner to lay against - makes for a little give of softness under the liner. Bottom lined with carpet padding to cushion and protect liner. My friends thought I was building a battleship - little bit of overkill - but wanted it done right and extra sturdy to begin with.
The covers are 2 x 2 primed and painted wood frames with 4 x 8 sheets of clear polycorbonate cut to fit and screwed on with galvanized screws with rubber cushions. Got the poly carbonate panels at Lowe's - I think in the $16 - $20 a sheet range - can't remember. There are 4 covers shown in the snow photo which are approximately 5 ft. by 8 ft in size butted up to each other. The frames themselves support the panel - they do not sit on a support in the middle. The only thing I did was to use a wide push broom to pull off any heavy snowfall so it would not put weighted pressure on the panels. Only had to do that twice a couple of times each day to keep any heavy snow from accumulating. Other snowfall was light enough I didn't worry about it. With the pond being 16 x 6 on the surface that allows for the cover sections (total of 4 sections equal 20 x 8 feet) to overhang and sit on the finish trim on the top of the pond so water runs off onto the deck and not into the pond. I simply open and prop up one panel if I want access to the pond to check on the fish etc. Pond temperature fluctuations have generally been about 1 degree F in a 24 hour period and no more than slightly over 2 degrees in 24 hours with extended periods of cold with snow and ice. I'm very pleased with both the panels and insulation.
The red Japanese rail I designed for my wife and let me tell you that took forever to assemble as I glued and screwed every joint. One of those projects you think will only take a day and turns into much more because of the detail. Well worth it though. Hope this helps explain and answer your questions.
Mike - thanks for the info!
Anyone out there using the heat exchangers shown on Kerin's site or the one's from AquaEcosystems - look like the same ones to me. If so how do they perform? Thanks