My releasers have always been outside. Yes, on rare occasions they froze, but only once was it a big problem. If you do as johnallin suggests you will likely have no issues. If the pump is remote from the releaser, just build a small housing around it and keep the releaser clean. That will help. If the pump is with the releaser, put them both in, but is gas, run the exhaust outside.
Dave Klish, I recently bought 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.