I have had 2 over the years, both run off my bulk propane tank. I started with a 1.3 gpm unit, it worked ok but I decided I wanted more flow. I then got a 2.3 gpm one and it is ideal. At 2.3 gpm it heats 35F water up to about 110-115F. I use a 120v Sureflo pump and use a ball valve to regulate the flow. I heat permeate from my permeate tank, after the season, I haul city water and put it in that tank. My Sureflo pumps about 3.3 gpm at full flow, that gives me about 100F. I use that for cleaning up, if more heat is needed I just close the ball valve (it is in the feed line to the HW heater) a little.
This is the one I have: https://www.sportsmansguide.com/prod...ater?a=1588404
You just need to remove a drain plug on the bottom to prevent damage from freezing in cold weather. It heats very well. If I ever change it, I'll get the next one up that uses 120V ignition rather than 2 D batteries. The batteries last 8-12 months with the use mine gets if on alk. batteries
Dave Klish, I recently ordered a 2x6 wood fired evaporator from A&A Sheet Metal which I will be converting to oil fired
Now have solar, 2x6 finish pan, 5 bank 7x7 filter press, large water jacketed bottler, and tankless water heater.
Recently bought another Gingerich RO, this one was a 125, but a second membrane was added thus is a 250, like I had.
After running a 2x3, a 2x6, 3x8 tapping from 79 taps up to 1320 all woodfired, now I'm going to a 2x6 oil fired and a 200-425 taps.