running 50 gals sap through a 2x4 drop flue possible?

[canaanmaple]

Just did a few test buckets last week, but been running ok, and now have 50 gals sap of 2.5% sap, so don't want to waste. I almost feel it's not enough to make it worthwhile running thru a 2x4 smoky lake drop flue hydrid since the flues hold almost 5 gallons liquid themselves. Some old threads suggested adding strait water to the back of the pan, and it will push the concentrated sap to the front of pan? Will that theory also work with a drop flue pan? Almost feel like I should be safe and go with chafe pans which I have also, but would love to do a test run on the 2x4.

also looks like the temps this coming week are still good for sap. Wondering what sugar content I'd have to take the sap to in order to keep from freezing at 27 degrees and just leave it in the pan till I collect more.

thoughts?

[Russell Lampron]

I would run the sap through the evaporator to get the pans sweet. If your season is going to start soon you can leave the concentrated sap/near syrup in the pans and wait for the next run. You could also drain the evaporator and finish the contents with your chafe pans. When I've pushed with water before It took a long time and a lot of wood to get finished syrup. It will work with a drop flue if you want to try it though.

What are chafe pans? I've never heard that term before.

[canaanmaple]

I would run the sap through the evaporator to get the pans sweet. If your season is going to start soon you can leave the concentrated sap/near syrup in the pans and wait for the next run. You could also drain the evaporator and finish the contents with your chafe pans. When I've pushed with water before It took a long time and a lot of wood to get finished syrup. It will work with a drop flue if you want to try it though.

What are chafe pans? I've never heard that term before.

Like buffet table pans. Supposed to get pretty frozen for the next two month, so not sure when the season will really start, so probably wont want to leave in the pan, but looks like the next few days the test taps are gonna run still

[wnybassman]

50 gallons probably isn't nearly enough to fully sweeten the pans, but it should get them sweet enough to sit for several days waiting for more sap, especially if it is cold/cool. Once sweet, I have run as little as 30 gallons before in my 18x60 just so it didn't go to waste.

Once the forecast looks cold again, drain everything out, clean it up and finish the contents as you would at the end of the season. If this is your first year with the rig, these will all be good learning experiences :D

[maple flats]

I also say run it, then shut down and if no new sap in a few days, drain it. Then either finish on something else or store it until more sap flows and put it back in the evaporator.
How many GPH are you supposed to get on that Smoky Lake set-up? If you get less than 16 gph the pans will not yet be sweet, if more than 17 gph they will be sweet. Fully sweetened pans in my experience can take at least 20 F without freezing, but will get some slush on top. If colder weather hits, either drain the pans or put a 75 watt incandescent bulb under the pans and a cover over the pans. That will keep everything from freezing.

[canaanmaple]

Once the forecast looks cold again, drain everything out, clean it up and finish the contents as you would at the end of the season. If this is your first year with the rig, these will all be good learning experiences :D

yes indeed! Wondering if I take 50 gallons down to 15 or so, if thats enough to keep it from freezing in the pan if temps get into the mid 20's. According to some charts, it seems like a 25% sugar content would lower the freezing point of water down to the mid twenties.

[canaanmaple]

How many GPH are you supposed to get on that Smoky Lake set-up? If you get less than 16 gph the pans will not yet be sweet, if more than 17 gph they will be sweet.

Interesting...curious why GPH affects the sweetening? (smoky lake claims it does 15-20gph)

[wnybassman]

yes indeed! Wondering if I take 50 gallons down to 15 or so, if thats enough to keep it from freezing in the pan if temps get into the mid 20's. According to some charts, it seems like a 25% sugar content would lower the freezing point of water down to the mid twenties.

You probably won't get 25% in the flues. With a drop flue you definitely want to be more careful about freezing. Even in my raised flue I put a heat lamp in the firebox when temp are much below 15º-20º for a long period of time.

[maple flats]

I guess the GPH really don't affect the sweetening, it is just the amount of water removed and even more the % sugar remaining when finished. I just use the GPH because lacking a good way to measure sugar in between 10 or 12% on the sap hydrometer up top about 40-45% or higher on a syrup hydrometer many can't test the sugar, Then you do the math. If you started with 50 gal at 2% and reduce it to 15 gal it will only be maybe 7% sugar. 12.5 would be 8% sugar. At 7-8% sugar you will get slush on the surface but it will not freeze solid in the mid 20's. Do not leave more than maybe 1/4-3/8" deep water in the pans or there will be damage as the ice expands.