help with slow evaporation rate

[White Crow]

I updated from a flat pan to an old 2x6 leader, it has metal pans with a drop flue and about 6" sides, I made a blower form a shop vac attached to a copper pipe with several holes drilled, I could not run the blower steady or the pan would boil over, I tried to maintain between 1 - 1.5 inches in the pan but only was able to get a 17 gal per hour evaporation, is this normal for this size evaporator, also this year it took 60 gal of sap per gal syrup, last year I had 34 gal sap to 1 gal, thanks for any advise

[motowbrowne]

I updated from a flat pan to an old 2x6 leader, it has metal pans with a drop flue and about 6" sides, I made a blower form a shop vac attached to a copper pipe with several holes drilled, I could not run the blower steady or the pan would boil over, I tried to maintain between 1 - 1.5 inches in the pan but only was able to get a 17 gal per hour evaporation, is this normal for this size evaporator, also this year it took 60 gal of sap per gal syrup, last year I had 34 gal sap to 1 gal, thanks for any advise

Sounds like you need to use defoamer. There basically shouldn't be any limit to how hot your fire is as long as you have sap in the pan.

I guess maybe I should be more clear. When you say "boil over", do you mean that foam builds up and will come over the side of the pan, like when a pot of spaghetti boils over? Or do you mean that the boil is violent enough that sap starts jumping over the side of the pan from the geysers that form in the flue pan? The first problem is solved by defoamer. The second problem will require a simple modification to your pan.

I had the second problem when I first got my 2x10. I started a raging fire and next thing you know my sap is jumping all over the side of the rig! I had a local welding shop make me a set of 8" side extensions that clip onto the sides of the pan. That solved 99% of the problem. I still losea few drops here and there, but not too bad.

Regarding target evaporation rate, it'll depend on a couple of factors. Is your flue pan 3' or 4' long? How many flues does it have, and how deep are they? Depending on these factors, you should be somewhere between 25-40 gph with your blower and good wood, I'd imagine.

[jmayerl]

Exactly what he said👍

[White Crow]

thanks, adding to the sides and the defoamer will be tried next season. I just measured the pans and both are 36" with 8" sides, the back pan has 8 drop flues in the center 2 sections at 6" with the 2 outside sections being flat, I had the hard boil that boiled from the center and over the flat part of the pan and out of the pan, the higher sides and defoamer should contain that, the front pan also boiled over a few times on me when I was getting close to drawing off, do you think the defoamer would contain that boil, can you send me a drawing showing how you attached the extension

[motowbrowne]

Defoamer makes everything better. :)

Foaming in the front pan is harder to manage than foam in the flue pan, but yes, defoamer will help. There is a danger of using too much and having the syrup quality affected, but I've never personally had a problem with it. I made about 105 gallons this year and used less than a stick and a half of butter. I add about the amount I could scrape off the stick under my index fingernail (no, that's not how I dispense it, just trying to get across how little it takes) to the flue pan every 8-10 minutes. I add it to the syrup pan only as needed. Some foam in the syrup pan is fine, but if it starts getting up toward the top of the dividers, I add defoamer. I use as much as I need to feel safe. No way I'm gonna burn my pan because I didn't add defoamer.

Also, butter is technically frowned upon because it's not a pure fat, and it's a dairy product. Atmos sells a dedicated syrup defoamer. You can also use canola oil. In my case, I sell all retail and my market is fine with butter. Honestly, they'd probably pay more for a separate batch with extra butter.

If the sides of your pan are 8" above the top of the flues, you may not need extra height. Perhaps try boiling water (which won't foam) at a full fire to see if you'll have problems with escaping sap before investing in extensions. Also with only a 3' pan, you could try something simple like baking sheets.

I attached a picture to show how mine are built. 1428314284

[adk1]

It sounds like we may have the same evaporator pans. I have two 24"x36" pans on my leader 2x6 and the same flue pan setup. I have forced sir under fire blower. I get about 40 all per hour boil rate. I run about an inch to 1.5 I would guess. The foaming will defiantly reduce your evaporation rate. What kind of wood are you burning and more importantly what size diameter? I split my wood at 20" long and down to the size of my wrist. You want a flash hot fire. I load a few splits every couple of minutes and never turn the blower off.

[White Crow]

thanks again for the info and photo, it is amazing how little butter you need to use for defoaming, I was thinking I bought an evaporator to small for 210 taps and started looking for a larger one but money is always the problem, I might even get stupid and tap more trees next year

[White Crow]

I had already cut mine short for my flat pan setup, 14" is what I had for this year with a mix between maple, cherry and pine, I did split to big and split some of it smaller as I was boiling, I was letting the fire burn down, not reloading wood until I noticed the boil slow down, I also had a problem on the flat pan where the center 2 sections would boil to a candy like boil before the drawoff side would reach temp. I was drawing off at 217, I tried to quickly add sap but the pan turned black anyway, it did not taste burnt but was close, I cleaned the pan for over a day and had it happen again within 1 week, sorry for all the questions, I never had these problems with the flat pan but I never would be able to boil the sap I had this year on the flat pan setup

[motowbrowne]

If you're a beginner on a rig like this, the best thing to do is find someone in your area running a similar machine and go spend a day cooking with them. It'll be worth it.

Best advice I got was to fire often (about 3 minutes on my 2x10), and only to open one door at a time. When you open both doors, you kill the turbulent flames, and cool the firebox. Open one door, fill it with as much wood as you can in the absolute minimum of time, and shut the door. Also, like was said earlier, split it small. Best fuel for a 2x is softwood with a little hardwood mixed in spilt the size of your wrist.

[doop]

Are you using a float box? By not firing regularly you could be ruining your gradient, and making syrup in places you don't want to. If you do forget to add wood and the fire dies down you can draw off for a few seconds to get things moving towards your draw off again then dump what you drew off back in syrup pan.

[White Crow]

thanks for the advice, my float does not seem to control the level as it should so I control it with a valve, I did loose the fire at times when trying to pump sap into the upper tank

[White Crow]

again thanks for all the replies with advice, I have a lot of softwood that I was reluctant to use and will split smaller for next year, I ran into a long time syrup maker at my grandsons ballgame tonight, I asked 1 question and he turned his back to the game and gave me a lot of advise, some of the same info received here, he did not see any of the game and his wife started to yell at him that we came here to watch the game, not to talk syrup

[Waynehere]

again thanks for all the replies with advice, I have a lot of softwood that I was reluctant to use and will split smaller for next year, I ran into a long time syrup maker at my grandsons ballgame tonight, I asked 1 question and he turned his back to the game and gave me a lot of advise, some of the same info received here, he did not see any of the game and his wife started to yell at him that we came here to watch the game, not to talk syrup

Ha, my wife does the same thing when I am out and someone asks how my season was. As for the foaming, I had a local producer show me to add a few drops in the sap pan every firing. That way it will keep the foam down in the whole rig as it works it way to the draw off valve. Only time I ever had a problem was at the end of the season and I got into some fermented sap. I had to add a little more defoamer and got it under control. The foam actually acts like an insulate and will slow your evaporation rate. So foam is bad, very bad... :) Plus it will help keep your sap level more under control.

If your float isn't working properly, I would try to get that resolved too. When you are running AUF, they recommend running your syrup pan a little deeper. I have a 2x6 and they say 1 3/4 to 2". You don't pull syrup off as often, but will pull longer when you do pull. Plus deeper will save your pans from burning. Lots of things you can try to have a better season...

[White Crow]

thanks, it appears the foam was my biggest problem, I like the idea of running a little deeper, I was trying to get a faster evaporation with the lower level but it appears the foam did not allow that to happen, my wife keeps asking the question... now how much did you spend, I usually "forget" to add all the items when I give her the amount, she is always happy when we are selling

[motowbrowne]

thanks, it appears the foam was my biggest problem, I like the idea of running a little deeper, I was trying to get a faster evaporation with the lower level but it appears the foam did not allow that to happen, my wife keeps asking the question... now how much did you spend, I usually "forget" to add all the items when I give her the amount, she is always happy when we are selling

How's the saying go? "My worst fear is that when I die, my wife sells all my syrup stuff for what I told her I paid for it."

Applies to other hobbies too...

[wiam]

How's the saying go? "My worst fear is that when I die, my wife sells all my syrup stuff for what I told her I paid for it."

Applies to other hobbies too...

I am baffled by the amount of times I hear this. Maybe I am doing it wrong but my wife knows what I pay for stuff......

[regor0]

I am baffled by the amount of times I hear this. Maybe I am doing it wrong but my wife knows what I pay for stuff......
No, your not doing it wrong. Your wife is just more understanding about such things apparently.

[motowbrowne]

I am baffled by the amount of times I hear this. Maybe I am doing it wrong but my wife knows what I pay for stuff......

I meant it jokingly, though the idea that these "hobbies" or small business endeavors are quite expensive is certainly true. I'm in your camp in this case. My wife came with and helped make the deal on our new cooker. We are partners in our LLC (maple syrup and vegetable farming), so all large purchases are made together. Small things, though might not be discussed. She probably doesn't know exactly how much money I have in chainsaws, for example, or wrenches and sockets, but if she really wanted to know, I'd tell her.

[mellondome]

thanks, it appears the foam was my biggest problem, I like the idea of running a little deeper, I was trying to get a faster evaporation with the lower level but it appears the foam did not allow that to happen, my wife keeps asking the question... now how much did you spend, I usually "forget" to add all the items when I give her the amount, she is always happy when we are selling

Running your pans deeper will only cause the foaming to rise farther and faster. The rise is caused by air needing to get from the bottom of the pan to the surface. The further it is to the surface, the more air you have in your syrup at a time. Which will raise the level further. If the air bubble cools too much before breaking the surface, the moisture will precipitate back into the surrounding syrup, slowing your evaporation rate.

[White Crow]

what level do you run your pans

[mellondome]

I have a raised flue.. so my back pan is just wetting the flue tops before boiling and the front is now at 3/4 in. ( starting with 18% concentrate on a 2x6. When I boiled raw sap I ran the front pan @ 1/2 in) If you like to run on the safer side ...then your looking at 1in with drop flue. No need to run deeper than that unless your pans are not level or have some really tall high spots from being hit with wood.
Fire on a regular schedule ( 5 to 7 min max) and add a drop or 2 of defoamer to the rear float box every time you fire.

When I first started using this rig, I was new to real pans. I ran it where the previous owner did ( 1 1/2in front and back ), used wood split for the house, and had no idea how to properly set up the inside of the arch. I was lucky to get 15gph. Over the course of 2 years, with lots of research, adding a preheater, splitting wood small and having it dry, firing every 5 min on a timed schedule, consistent defoamer use, adding lots of air under the grates, rebuilding the arch inside, I would consistently get 55+gph. Forgot to add.. lots of trial and error. If you have time otside of season to work on tweeking your evaporator and process ( boiling water), it will be better than trying things during season.

[White Crow]

thanks for the info, I have received so much info, I only wished I would have asked after the first week of boiling and the big disappointment with my evaporator, I have several improvements planned for the summer and can not wait for next season, do you use a steam hood to get to 55 gal per hour, if I could get that I would tap more trees

[Sugarmaker]

Well you came to the right place to get comments and suggestions about your evaporator and making syrup.
Couple things;
I think in another 30 years you may have all this figured out!:)
First you rig should boil on average about 30 gallons of sap per hour. How and when you measure that is important.
Second You are having way more than average gallons of sap to syrup ratio, Should be about 44 to 1 with 2% sap. You need to start checking that too as a reference. If you really are getting that swing I would have a serious talk with the trees!
Third if this is your first year on this continuous flow then yes making syrup in the center partitions can happen. You will need to move some sap towards the draw off and or fire more kindling on the side you are draw off on.
Consistant boil as mentioned is helped by firing every 5 minutes or so.
Yes defomer: couple drops in the flu pan and one at the draw off port each time you fire will help keep the foam down and the syrup moving.
Get the float working It helps the evaporator run better.
Have lots of fun making syrup!
Regards,
Chris

[White Crow]

thanks again, I may start talking to the trees now, I hope to go to stainless in another year, maybe a 2x8, 30 gph is what I was really expecting when I bought this unit but I made way to many mistakes, I will be taking the float apart, it slows the flow down, and then it will flood the pan if I don't keep watching the level