Evaporation Rates on Homemade Arch

[tjintheshop]

Folks

I know that evaporation rates are not an exact science but I have a fire boarded and bricked 2ft by 78in homemade arch. I did install an old furnace fan under the grates and plan on running some copper tubing around the stack as a preheater. I have a 2 by 30 inch divided syrup pan and just ordered a 2 by 4 flat pan for the back (Couldnt get a flue pan done in time for this years run).
What type of estimated evap rates would a guy come to expect out of a rig like this? My pan wont be done till late next week so kind of anxious I guess.

Also,
Is 285 bucks a decent deal on the pan? Its 2x4x10 inches deep made out of 16 gauge SS. Two handles on each side with 3/4 coupler. All welded.

Thanks

[Toblerone]

I would say about 1.5gal per sq ft max. So you have 13sqft * 1.5 = 19.5 gal/hr max. I have a 2x6 flat pan and I get only about 16 gph on it, but my wood is not well seasoned or split. I'm hoping a preheater will help, but in theory the most it could help would only be about 2 or 3 additional gph.

And $285 sounds like a good deal to me, but others would know better.

[len]

I believe that the general rule for evaporation rates is 1 ft^2 ~ 1 gal/hr. Optimizations in the internal firebox, and shelf area, as well as air under/ over fire will bring the boiling rates up.

[jmayerl]

I would say that was a really good deal for the pan. I had one made my Jim schumacher in little chute and paid a little more, but it was a last minute deal and it also has a center divider and 3 3/4 ports

[Flat Lander Sugaring]

I have a 2x6 split evenly with a drop flue , old furnace oil gun for air under and a home made preheater. In the leader literature it said I was to expect around 24 gal/ an hr, with modifications I am doing 34/36. I would say Toberlone is really close.

[len]

I have a 2x6 split evenly with a drop flue , old furnace oil gun for air under and a home made preheater. In the leader literature it said I was to expect around 24 gal/ an hr, with modifications I am doing 34/36. I would say Toberlone is really close.

Do you have a total ft^2 value for your rig pans?

With my tiny hotel pan experimental rig, after adding air over, I was able to get an evaporation rate of 2.6 gal/ hr, with a pan area of 1.6 ft^2. This is a factor of 1.62*(pan area), so I don't think a factor of 1.5 is the max obtainable. A preheater would increase the rate further. Before adding air over, I was at 2 gal/ hr, then I added air over, and got 2.3 gal/ hr, then I opened up the flue area, and got to 2.6 gal/ hr.

[SeanD]

tj,

I have a 2x6 with two 3-foot flat pans. Last year with natural draft I got a peak of 24 gph during the boil, but averaged out from lighting the fire to shutting off new sap coming in, it was 17 gph. that was on a block arch. With your draft and a tight, bricked evap. you should do a little better.

Sean