After you have gotten a little use from it on water drain completely. When you start your season, you want between 250 and 300 gal of sap before you run the first fire (or what was that much sap before running it thru an RO). That is what you need minimum to sweeten the pans. Once sweetened, they don't need to be drained unless a hard freeze is forecast (like 10 F or colder) Slush will form on the top but it will not freeze solid.
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.