sap level

[CTsugarMan]

What would you all suggest is a good level of sap to be boiling...1 inch or 3-4 inches, I have two flat pans in a barrel stove.... thanks for the info

[mapleack]

The lower you go the faster the boiling rate. That said I'd imagine less than a couple inches would be scary in flat pans due to not having a float valve feeding it. I run 1/2 to 3/4 inch in my flue pan and about 1 inch to 1.5" in my syrup pan.

[happy thoughts]

I'd keep it low. The big guys run 11/2 to 2 " deep and there's no reason that wouldn't also follow for smaller pans. When I did steam pans on a camp stove, the evaporation rate was always better when run shallow. Also, depending on the depth of your pans, I wouldn't want to boil anything close to near syrup 3-4 " deep. You might be risking disaster there if the boil gets away from you.

During my first time experience the other day on a 2 steam pan block arch, I ran the hot pan no more than 2' deep, I ran the cooler sap pan a little deeper, at about half to a little more than half full in 6" deep pans. That seemed about right to me and I'll probably do the same again the next time I boil.

[Burnt sap]

I run 2.5 in my pan that seems to net the best on my set up with about 2.5 gallons in the pre heater.

[3fires]

I could run mine deep with steam table pans because they're sunk in and the sides are getting flames too, but I think a good all around number is 2". I didn't like over 2" for finishing as, like happy thoughts suggested, it can boil over real quick and then all that hard work goes down the drain...or all over your hands. Ouch!

[waterfowlah]

I tried all different depths this past weekend. 2.5 to 3" seemed to work the best for me.

[CTfarm]

I run my flat 2x3 at about an inch. Adjust my preheater to equal what is being evaporated. Works well with my set up.

[Greg Freeze]

Ditto CTFarm. I try to keep my 2x4 between 3/4" and 1"

[Vermont Creation Hardwood]

I run flat pans and do batch boiling. I finish the syrup inside. I fill the pans full and let them boil down, then fill again, till I run out of sap. The advantage is that I don't have to pay close attention to the boiling and can be doing other work. Just feed the fire regularly. I never use defoamer because this way it doesn't foam. When all the sap is boiled and it's getting low in the pans, it's time to pay closer attention. I boil as low as I can, letting the fire go out as the sap level approaches 1/2". I work it so the fire is out by the time the level reaches 1/2", then empty the pans into a stainless bucket. I filter it as near syrup out of the evaporator, then filter it again when syrup inside on the stove. Near syrup filtering goes fast yet removes much of the sugar sand and makes the final filtering faster. Finishing on top of the stove allows more attention to be paid at this stage and very little attention needed on the evaporator.

For the small producer, the advantages of batch boiling: do other things during the majority of the boiling process. I hate to sit around, have many other things that need doing. Never need defoamer. Finish on the stove in one or two gallon batches of syrup. Here more attention can be paid and the hydrometer assures consistent syrup.

[Greg Freeze]

Laid back is another method like VHC said. I guess the difference is some us boil off as rapidly as possible and others take a less aggressive approach. I run it so low because I'm running a nearly out of control boil and stoking the fire every 5 minutes with a fan pushing it through. I constantantly monitor my flow in, but I have to stoke the fire anyhow. I can't and don't leave unless somebody is there to watch it. If my preheater line plugged, I'd probably run the pan dry within 15-20 minutes. :cry: But VHC has me thinking that if, I had other things I needed to do, I could just run more sap in the pans and boil less aggressively. Still might make me nervous though.

[CTsugarMan]

thanks all, i do what VCH does, this way i can tend to the other things in the yard... thanks again

[Treetapper]

If your pans are sunk into fire box you need to keep your sap level above the flame line or you will get scortching on the sides of your pan and have a burnt flavour in your syrup. It could also distort your pans if not kept at or above flame line.

[Stamford sugarmaker]

Although VCH doesn't say how deep his pans are, I would expect they must be about 5 or 6 inches deep. It seems to me the heat energy required to boil that volume of liquid would be enormous. Look at it this way- would you want to boil using a pan full of sap that was ten feet wide, ten feet long, and 10 feet deep? If you did that, you could probably build a house with the spare time created! (: (:

Running your sap at 3/4" or 1" deep would minimize your wood and time consumption in the long run. That's my take on the issue, for what it's worth. If anyone has tried doing it both ways I'd be interested in hearing about your first hand results of the comparison.

Peter

[Vermont Creation Hardwood]

The energy required to evaporate the sap is the same no matter how deep you run your pans. With a flat pan why spend all your time watching it boil when there is no need to? One of my flat pans is divided. It actually runs more efficiently with the pans full since the dividers conduct heat into the sap, as well as the sides. Without sap against the full height of the dividers and the sides, you are losing some of the conducted heat through the stainless to the air rather than the sap. I don't imagine it's a huge difference, but it may be significant.

My way the evaporation of sap actually takes less of my time, since I'm not spending that time sitting at the evaporator. I'm doing other things, gathering sap, cutting firewood, building furniture, keeping the stove in the house going, eating, even napping. My pans never foam. I need only pay attention when the sap gets low and I'm getting near.

[Treetapper]

If his pans are sunk into the fire box, then he really has no option but to run his sap level at or above the the point where the pan enters the fire box or the pans will get scortched from the exposed area not being covered (at the sides) by sap.

[Stamford sugarmaker]

VCH,

Interesting concept of the heat transfer through the dividers and sides of the pans. It makes sense, I wonder if it's a measurable difference?

How often do you fire?

Peter

[Vermont Creation Hardwood]

I fire whenever I remember to, perhaps every half hour to an hour. My approach seems to be much more laid back than that of others. I have plenty of other things to do, so sometimes I get distracted and don't feed the fire often enough. When I'm boiling I'll run the evaporator all day and all night, it there is enough sap. Often I'll get up at times in the night to feed the fire. With my bed of ashes, the embers remain hot enough to rekindle wood for up to 24 hours.

I'd rather not have evaporating be a frantic rush, but an efficient dance between other areas of work and feeding the fire. I don't waste time. Sitting and watching the fire is wasting time for me, unless I'm taking a break and breathing the sweet, sticky heat of the moment.

[Big_Eddy]

It's all about balance.

I batch boiled on a 2x3 flat pan for 20+ years using the same basic setup.

If I was ahead on sap, I'd fill the pan to 4-6" and I would evaporate ~4 gallons an hour, stuffing the arch full of wood every 20 minutes or so. Made for a pleasant day outside puttering and at the end of the day I'd have 1-2 gallons of syrup and the wood pile would be the same size I started at. I could leave for lunch, collect sap, go get wood and it just kept boiling.

If I got behind on sap (Work always seems to be busiest when the sap is flowing) I'd run the pan 1-2" deep and fill the arch half full every 10 minutes. I'd evaporate 6-8 gallons an hour, but I had to have wood at hand and I never left. At the end of the day I would have boiled up to 100 gallons and made 2-3 gallons of syrup, but my wood pile would be gone.

It depends what is important to you. Running shallow and firing often will up the evaporation rate, but you need to stay close. If you're not in a hurry, run deep and fire when you want and enjoy the day. Interestingly - I never noticed ANY correlation between grade of syrup and firing rate when batch boiling. Early runs were light, later runs would end up amber.

With my new evaporator, I run at 1- 1 1/2" and fire hard till I want a break, then let the fire die down while I step outside. At 18-20 gallons an hour, I'm not spending anywhere near as long boiling as I used to so I still have plenty of time to collect sap and cut more wood.