Front Pan Vs. Back Pan Boil Rate

[warners point]

I did my first test boil on my 2x6 yesterday. Everything went great. The only thing that concerned me was the speed at which the pans came to a boil. The back flue pan with copper drop tubes was at a rapid boil 10 minutes after I lit the fire. It took the front pan over 30 minutes to come to a boil. Will I run into a problem with the back pan evaporating off too much water and make syrup back there? Should I add some fire brick to the back of the fire box to keep the heat up front longer? I already added another 3 inches of brick to bring it up to the bottom of the tubes.

http://i297.photobucket.com/albums/mm207/bedublu/Maple%20Syrup/IMG_2138.jpg

[buck3m]

That's a very interesting design and you should be proud it boils hard.

It seems to me that as long as you have the sap entering your flue pan and moving on to the syrup pan that most likely you won't have your "syrup in the flue pan" problem. It would pay to keep an eye on until you know for sure, though.

Hopefully someone with experience in evaporator design will add something.

[maple connection]

I just modified my 2x6 because it boiled to hard in the flue pan. I have a 14" smoke stack with a damper in the pipe, So I cut back the damper and added a blower. I directed the air to blow threw the grates and up toward the firing doors. I tryed it on Sat. and my front pan now is boiling just as hard as the flue pan.

[BryanEx]

I have to ask about the numbering on your fire brick. Is that for your cutting & fitting or do you expect to be able to see it after using the evaporator for a season?

[warners point]

The numbering on the bricks was because I put the evaporator together in my nice warm garage and then hauled it to the frigid sugar bush that has no power or heat:)

[BryanEx]

Let me know if that numbering is still visible after a maple season. I would love to dry fit brick and mark each location but can't see it working.

[WESTVIRGINIAMAPLER]

Normal for you to get a better boil in the back pan before you do in the syrup pan as there is so much more surface area back there and the arch has not got heated up good yet either. You could boil back there for hours without any syrup going into the front pan and not run into any problems.

[RileySugarbush]

So what was your overall rate?

[warners point]

I only did a water test as we didn't have enough sap to boil yet. I ran it for an hour, 30 minutes of which was a hard boil and I added 20 gallons of water to it. I'm glad I have 12" sides because those tubes can really spit.

[PerryW]

Normal for you to get a better boil in the back pan before you do in the syrup pan as there is so much more surface area back there and the arch has not got heated up good yet either. You could boil back there for hours without any syrup going into the front pan and not run into any problems.

Agree w/ WESTVIRGINIAMAPLER. My back pan come to a full boil in about 7 minutes; but it takes the front pan much longer. Once the evaporator has run for a while, a bed of coals will develop under the front pan and it will start boiling better.

[WESTVIRGINIAMAPLER]

You will learn how to fire it better and get it boiling quicker. If I fire mine right, I can have both pans boiling in about 5 minutes.