A Look Down the Evaporator Chimney

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Caw

Minister of Fire
May 26, 2020
2,553
Massachusetts
I was dismantling my evaporator for the season and thought it would be fun to look down the chimney before tossing it. This is a simple piece of 6' x 6" ducting used in a cinder block/fire brick arch. I ran about 4 pick up truck loads full of old pallets through it burning hot and fast. Pretty nasty. Soot everywhere, including the non-fire brick lined portions of cinder block and the chimney where the smoke could condense easily on the cool blocks. I got pretty dirty disassembling it. Anyways thought it was interesting!

Actually that reminds me...any good remedies for getting soot off yourself easily outside of soap and elbow grease? That stuff really gets in there in your hands/clothes.

PS - got a little over 2 gallons from 16 trees. Product was good, evaporator works well, just a crummy season volume wjse!

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Every year I say "we should tap some trees" and then before I realize it, the season is over. We don't have any sugar or black maples in our immediate vicinity, but we do have Norway, red, and everyone's favorite... box elder. So, if I ever do get around to tapping trees I will need even more sap to make syrup. I think it is 3X the sap compared to sugar or black maples. 2 gallons is still a lot of syrup.
 
You need more sap but it's not that extreme a difference. With sugar and black it's about 40:1 sap to syrup ratio on average. Reds and Norway more like 50:1. Not sure on Box Elder, but they are tappable. Every tree is different though, some have more sugar than others. I tapped Reds and Norways this year and was around 45:1 on average over the season.
 
You could add some more firebricks next year or make it more like a rocket stove than a enclosed fire for less smoke.
 
Not looking to spend another $100-$200 on it right now...I'd invest that in a bigger/nicer pan if I did. I use firebrick on the bottom and masonry brick on the sides. It only really smokes on reloading because I'm using old pallets which can be dirty sometimes. (I toss painted or stained ones). Pretty sure the wood is the culprit. A lot of the time I do get the rocket stove effect....had flames 3 feet out the chimney last boil!
 
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That's a pretty cool setup. how many taps do you normally put out, and how much finished syrup do you usually produce?
Below is what i use. it's an old welded steel stove the previous owner left in my barn. I cut a hole in the top with an angle grinder, and dropped in a stainless steam tray pan. i only have about half a dozen sugar maples on my property, but they're big ones, and they produce more than i can keep up with. I use 5 gallon water cooler jugs, with a plastic tap and 18" of tubing fits perfect into the top of the jug. in 1 week i can easily pull 40 gallons of sap, which is all i have time to boil.
Sorry, hope i'm not in trouble for turning this forum into a maple syrup forum?
 

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This season I did about 115-120 gallons of sap into 2.25 gallons of syrup of 10 red and 6 Norway maple trees. It was a terrible season for the reds so much less than I expected...80% Norway sap... but the syrup is very good.

This was the evaporator 2.0 that I upgraded halfway through the season. My first one was very rudimentary and while it drafted all, it allowed too much heat to escape. I redid the interior to include the firebrick and masonry brick I described above and configured the blocks to allow me to recess 3 buffet pans like you have there. I could easily handle 40 gallons a day if I started at 9 am...it just eats wood if I want to keep the boil rolling hard. I used about 3 full pickup loads of pallets. Shoveled a lot of nails out at the end!

Adding some "modern" stove tech like a take chimney, firebrick, and making it as airtight as possible so it would suck air in through the coals made all the difference. It burned much hotter on less wood and stayed hotter longer than my initial design. Next year I may add a baffle block 1-2 ft before the chimney as an experiment we'll see. Im not sure it needs it tbh. Also I think expanding the channel for the smoke to get into the chimney may help a little with the mess. Easier flow, less leakage into the blocks and pans. Lots to experiment with and improve.

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I think this thread is very interesting and it is a asset to this forum so no worries..--my opinion...How in the world did you get into this syrup making from trees that's my question of this day...You could very well teach people about this type of making syrup--have classes and charge a small fee..people would attend and be very interested in something like this--maybe even soap making as well with all the "organics" people like to buy--you just keep on talking about wood and stoves and ideas and most of all sharing your home made syrups and tree types as well...good for you--keep talking--I give you a A plus.. clancey
 
Good for you CAW, sounds like a lot of work, but well worth it in the enjoyment of the process and another step in being self sufficient. It would take us a couple years to go through 2 gallons of syrup. We don't have any maple or box elder trees on our property, but I'm going to keep an eye out for them when I'm hunting for morels and consider trying it next year.
 
With two kids under 6 we go through copious amounts of syrup. Probably around 3 gallons a year or so. I usually get it from a family friend who taps 3,000 trees in northern VT. Still going to get my usual 3 gallons from them it doesn't go bad! Maybe take a syrup bath lol.
 
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I finished off my final batch today and made 6 pints of MA Super Dark! Here's a pic comparing it to the mid season Amber. That's a wrap on the season!
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They both look really good and enjoy and relax now a bit and get ready for a beautiful Spring and Summer---"Yes"...clancey
 
I finished off my final batch today and made 6 pints of MA Super Dark! Here's a pic comparing it to the mid season Amber. That's a wrap on the season!
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I've always preferred the stronger tasting Grade B dark syrup.
 
Never thought of syrup on pecan pie. Isn't that just putting more sugar on top of basically pure sugar with a few nuts mixed in? I'm not a big sweets guy so that doesn't sound good to me lol.
 
Never thought of syrup on pecan pie. Isn't that just putting more sugar on top of basically pure sugar with a few nuts mixed in? I'm not a big sweets guy so that doesn't sound good to me lol.
LOL, not ON pecan pie. I think you already answered my question, since you don't like sweets. Let me ask another way, is it anything like dark Karo syrup? (it's a main ingredient in pecan pie) ;lol
 
Haha whoops! Gave myself away didn't I ;lol.

To answer your question though they are very similar but different.

Scientifically pure maple syrup is mostly a sucrose solution. Just pure natural water/sucrose boiled down to 67% concentration. Corn syrup is 100% glucose. Dark just means it has molasses added to it. So, being different sugars, they will behave differently in certain recipes.

From a cooking point of view there are other differences. Karo is thicker and it doesn't have much taste...just sweetness (dark will have molasses taste). Dark maple syrup is a little thinner but has robust maple taste with all sorts of other complex earthy flavors mixed in.

So yeah you could definitely use one in favor of the other for pie I think. Candy I wouldn't substitute tho as those sugars crystallize at different points. You'd just have to be ok with making maple tasting pecan pie because that molasses taste will be gone! It would be a curious experiment! I'd probably try a 1:1 ratio and see how it comes out. My guess it might be a touch thin but pretty good.

I think the thickness throws a lot of people off when they first experience real maple syrup. The imitation pancake syrups like Log Cabin or Aunt Jemima are thick...because they are just light Karo syrup with artificial maple flavoring. Real syrup is still a thick sticky liquid but a little thinner than corn syrups. I know tens of millions or more people love "pancake syrup" but having grown up on real syrup I just find the stuff revolting!

My wife loves pecan pie and basically all sweets. I have a token piece every year. I get sugar overload after a few bites! The only time I really go nuts with sugar is with real maple syrup. Pancakes and waffles for days!

Full disclosure I am a scientist but not a baker ;lol.
 
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For many years a friend made us HM Southern Pecan Pie and I always thought it was real maple syrup that it was made with but I could be wrong but even the mention of it brings back memories...I buy real maple syrup in the store and I am sure it is thinned down but oh what a wonderful taste compared to the others---more money too--but I sure do love it...clancey
 
Haha whoops! Gave myself away didn't I ;lol.

To answer your question though they are very similar but different.

Scientifically pure maple syrup is mostly a sucrose solution. Just pure natural water/sucrose boiled down to 67% concentration. Corn syrup is 100% glucose. Dark just means it has molasses added to it. So, being different sugars, they will behave differently in certain recipes.

From a cooking point of view there are other differences. Karo is thicker and it doesn't have much taste...just sweetness (dark will have molasses taste). Dark maple syrup is a little thinner but has robust maple taste with all sorts of other complex earthy flavors mixed in.

So yeah you could definitely use one in favor of the other for pie I think. Candy I wouldn't substitute tho as those sugars crystallize at different points. You'd just have to be ok with making maple tasting pecan pie because that molasses taste will be gone! It would be a curious experiment! I'd probably try a 1:1 ratio and see how it comes out. My guess it might be a touch thin but pretty good.

I think the thickness throws a lot of people off when they first experience real maple syrup. The imitation pancake syrups like Log Cabin or Aunt Jemima are thick...because they are just light Karo syrup with artificial maple flavoring. Real syrup is still a thick sticky liquid but a little thinner than corn syrups. I know tens of millions or more people love "pancake syrup" but having grown up on real syrup I just find the stuff revolting!

My wife loves pecan pie and basically all sweets. I have a token piece every year. I get sugar overload after a few bites! The only time I really go nuts with sugar is with real maple syrup. Pancakes and waffles for days!

Full disclosure I am a scientist but not a baker ;lol.
I gave myself away, by not knowing the difference in syrups.:) I'm one of the 10 trillion that grew up with the Log Cabin and Aunt Jemima brands. I didn't have the enjoyment of real maple syrup until about 10 years ago, and we don't have kids at home to devour syrup by the gallons. Your description of the dark maple syrup makes me want some, it's on my watch list. Traditional pecan is probably my favorite pie, maple tasting pecan pie sounds good, not sure how the texture would be though with the thinner syrup as a base. But, it would be worth trying. I'm not a picky eater, I'm sure I'd enjoy it no matter what.

We were at a Mennonite store last week and they had some kind of maple syrup they were really proud of for $54/gallon. It sounds expensive to me, but I really don't know what it's going rate is.

On a side note, there was a post about hickory trees a couple months ago, but @Grizzerbear mentioned his grandmother (?) made hickory pie that he really liked. We have a lot of hickory trees, and I hate the nuts all over the ground, but maybe I'll give it a try this coming fall.
 
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@MoDoug yea it's the same as a pecan pie but substituted with hickory nuts instead of pecans. She makes her own crust with lard and man let me tell ya.....it is excellent. I agree though that the hickories leave a mess. I have one right outside the fence of the yard and their are so many hulls underneath it the grass won't grow.
 
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