So I have a 400 gallon cattle/stock tank that has been my kid’s “kiddie pool” the last 5 years. Anyway, have some old copper and thought about making a thermal hydro lifter. I was thinking to heat water in my greenhouse, and/or turn that kiddie pool into a wood fired hot tub. Maple and Doug fir and fruit limbs are in over abundant supply. Plenty o fuel.
Anyone here ever been hands on with one of these wood fired thermal water lifter heaters?
Something like this: External Image
One thing I can tell you….its a lot more difficult to get heat exchange with something like this than you would think. If you did do it you would want some way to create turbulence in the water going in- if you used a holding tank you could recirculate to raise temps but gonna be difficult with one pass or the flow would really need to be slowed down. Also- beware of the tube exploding or getting burned w steam.
If that’s an actual picture you would definitely need insulation and a cover. @noddykitty1
Those are pre fab sold kits in the pic. One is $5000 dollars with the tub and a cover. the other one is $700 us for just the stainless steel heating coil with bulkhead fittings and quick connectors. Lots of YouTube videos showing these in action. Lots of homemade ones w copper.
I have seen coils like this the size of a lunch box make a 40 gallon old hot water tank boiling hot in an hour at boy scouts camp. So I know they work in therory. I have watched a couple videos of that too. I just never blew the size up in my head and had the idea to hook it up to a hot tub.
Tips on the DIY versions mentioned steaming if you don’t use thick enough copper, too hot a fire, and have both the intake and outtake not parellel but deep and shallow. So pulls the cold from lower o the water column. I was surprised if it was not camera tricks how much flow there was with just thermal convection. Also, many mentioned insulating the sides if they used it a lot.
@noddykitty1 might check into homebrewed beer forums or shops online for counter flow chillers…will also work to heat in reverse. Can also be made- they charge an arm and a leg for the copper ones.
I know this is a late reply but you may still be interested. You should definitely use a shield/cover as others suggest. Not sure how much you want to spend but you can install a temperature control valve and pressure/safety relief valve (keeps your tubing intact and bursting). This sounds complicated and expensive but they make self contained devices you can easily spec off the net. Not sure if it is permissible to say but Grainger will have everything. You can probably get by fairly cheap.
