Expected GPH on Oil Tank Evap?

So, I posted this on other thread. Wanted to get a few more people looking at this. What are you guys/gals (using 275 gallon Oil Tank Evaps) getting for GPH evaporation rates?

I finished mine two weeks ago, did a test boil with water and just did the first "real" sap boil on it Monday. Started with roughly 50 gallons and got 1.5 gal finished syrup.

Did 3 timed tests (as scientific as possible) and was getting 12-14 GPH average! One sample I got 16GPH!!!

This normal? I'm not complaining, believe me! Just curious if it's typical for this type of setup...
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Better than mine. I get 10 to 12 depending on how good I am about paying attention to the fire. How deep are you running the sap? Blower?

6" pans running 3-4" deep depending on bubble ferocity... Blower (you can see in my gallery) is off our Pleasant Hearth Medium wood stove (they sent replacement and we are using the old one) runs about 100CFM best I can tell.

Rule of thumb is a gallon of evaporation for each sqf of if your running a flat pan . I to have an oil tank evaporator and this will be my first season using it I've got a CDL 2x4 in the back and a full size steam table pan up front should give me about ten sqf of pan so I'm hoping to get a gph of 10-15 and I will be adding a blower .

I think the 42' preheater coil is the biggest contributor. Everyone else I see has only 10-20' (guessing by sight).

At full tilt, the sap coming out of the coil its so hot you can't even touch it.

I am so excited for this season!

I don't man 16/hr off that pan seems a bit high. Be interesting to see how your season averages out.

I took 4 15min samples. 1 was 16/hr so I threw that one out of the average.

The other 3 sample points averaged at 12-14gph. It's not like the math is hard... Preheater holds 4 gallon. Had to fill every 15-20 min with 4 more gallon.

I fabricated an oil tank evaporator and lined it with 1" ceramic insulation and layered fire bricks over that. I run a blower(actually from a dehimidifier fan). My sap feeds into a 24" X 12" preheating pan which gravity flows into a copper tubing shower that trickles hot(170 -190 degree) sap into the main pan which is 24" X 60". I use only hardwood.I just Installed an actual wood stove door and insulated it. last year w/o the new door I would get between 18 and 20 gph as long as I kept up with the wood and maintained a constant boil. The sap pre-heater made a huge difference I think it increased the rate about 3-4 gph. Here's a couple of pix, it doesn't show the copper tubing on either one I don't have current pic of it. Good luck with yours!! Have fun trying I do! Some day I might have enough $ to buy a real evaporator.

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