raised flue - drop flue

[Brent]

I using a Leader Half Pint with a flat bottom and want to spend less time boiling next year with more taps.

Yesterday I saw a DG "sportsman" drop flue model.
1) the fire box was smaller that the Half Pint ... that really surprised me.

2) how do you get the sap/syrup out of the dropped flues. They all seemed to be below the discharge level ???

If I want to boil fast on weekends only, that would seem to me to be a problem because I do not want to leave sap in there all week, do I ???
It would seem to me a raised flue would drain and clean easier.
Never seen one working yet so I'm only trying to imagine it.

[Jim Brown]

Brent; I used one of those last year. For what they are they work pretty well. 10-12 gallon per hour. You are right about the flues they are below the drawoff. The only way to completly empty is to tip it over, We just left the concentrate in the rig till we were done.We covered it with a piece of plywood and left her set till we had sap again. the only thing you have to watch out for is that it may freeze hard enought during the down time to crack the flues if the concentrations in not strong enought. I now run a 2x6 with a steam hood and we are looking to put a steamawy on it for next year.
Hope this helps
Jim

[brookledge]

Most drop flue pans that I have seen have a drain that comes out the side of the arch that has a valve on it so you can drain it. During regular boiling the sap concentrates and keep moving along and into the syrup pan don't worry about the sap below in the flues while boiling.
As far as raised flues you still need a drain valve to get the sap out of the flue pan.
Keith

[Rob Harvey]

Our drop flue does not have a drain in the flue pan, so when we want to drain it we just syphon it out into buckets. Rob

[Banjo]

Brent,
thanks for asking this, I've been wondering the same things.

I'm thinking that for "occasional" boilers where you'd like to boil down everything you get that the raised flue could be better since you can drain it out more easily.

Any opinions on any "sweet spots" (no pun intended) on evaporator size, flue depth, and the like that allows you to boil at a reasonable rate, while reducing (or ideally eliminating) the amount of "in process" sap?

Just using the pot method right now I just boil up and finish everything in a batch. I'm starting to realize that this process is not what's done as you move to larger evaps.

I'm currently thinking that a smaller evap pan (sort of half pint size) with small raised flues (maybe 1-2" high, 1" or so width), coupled with a flat finishing pan (or maybe even sticking with the separate propane finisher) might do the trick for 50 taps or so.

Thanks again for everyone taking the time to comment.

cheers, Andrew

[Brent]

Andrew

I think we're on the same page here. I want to, ( need to ) process small batches. The D&G Sportsman I looked at yesterday had no drains for the flues. Furthermore one would not have been enough. Each dropped flue was independant.. The unit had a division down the center about the sap level, like the Half Pint ( that has 2 divisions )

A U shaped pipe connects the flue pan to the finishing pan which is flat bottom.

Raised flues would be much easier to drain but if the tops came out of the sap you'd scorch them.

Pro and cons.

[maplehound]

Andrew,
When it comes to scortching a pan. I think the raised flues is better. My first rig was a 2x6 drop flue. It took 2 people to take the flue pan off the arch and dump it, to empty the flues. The rig I now have is a raised flue and it has a drain on the pan at the bottom of the flues. In larger drop flued pans there is also a drain to drain the flues completly that extends outside the arch. The big diffrence here is that in a raised flue you have 2 float boxes. One for the flue pan and the other for the syrup (flat bottom pans.) The float in the flue pan is set to 3/4" over the top of the flues. As long as the top of the flues stay wet there won't be anyproblem. I have a friend who has a raised flue and his sometimes barly has the sap splashing on the tops of his flues with no problems at all.
Ron

[WESTVIRGINIAMAPLER]

I think on any current manufactured drop flue 2x6 and up, there is a drain on the flue pan. :) Anything smaller than that is a hobby size and they cut corners to cut costs! :?

[Brent]

what does it take in gallons to do an initial fill on a drop or raised flue unit.

I am wondering if my tap count would be enough to support one. I do want to start treating sap with UV daily as we bring it in and store it for boiling on the weekends, if we can find a good workable game plan to do this.

[Father & Son]

Brent,
My son and I just got into sugaring last year. We purchased an old 2 x 6 leader drop flue with tin pans. It is old enough that there is no flue drain. We left everything in the pans between boils most of the time. The only time we drained it was when there was going to be a long cold spell. I was worried that we would freeze the sap in the flues and split the solder. I was told that freezing and splitting was almost never a problem to not worry about it but with my luck I like to be better safe than sorry. The way we drained the flue pan was to syphon each flue into a bucket like posted before. Our flue pan is 2 x 3 and at a depth of 1 1/2 inches it holds about 7 1/2 to 8 gallons. The front pan is also 2 x 3 and at the same depth holds about 4 gallons. Hope this helps :)
Jim

[Brent]

Thanks for the comments Jim

Sounds like the post above is on the money. The hobby class currently made don't have the drain(s) I would like. Maybe a light bulb in the fire pit on cold nights would be enough to give me comfort.

What do you get for gallons per hour on a unit like that ??

[Father & Son]

Brent,
I did use a quartz work light in the fire box and covered the base stack outlet a few nights and nothing froze. Worked well. We were getting 20 to 25 gallons per hour and put a blower on it this year and got alittle over 30 gph. A longer flue pan will increase your gph. The newer 2 x 6's have a 4 foot flue pan.
Jim

[Brent]

It's 9:00PM and I just got back from the bush. took in 135 gallons today.

The Half Pint is looking at 85 in storage right now. Non-stop and we'll be caught up by 9:00AM.... just in time for tomorrow's.

At 60... I can't get there from here.

[WESTVIRGINIAMAPLER]

Jim,

You can take some newspapers and a few pieces of small wood and burn in it every couple of days for a few minutes and it will do the same.

Light bulb works great. Main thing is to make sure you close off the draft so the stack is not sucking cold air thru the flues 24/7 :)

[maple flats]

On my 2 x 6 I was told by the dealer to get at least 3 hrs boil time worth of sap before boiling. Then just fire it up and shut down before you run out of sap, in my case I boil 22-25 gph and shut down when I have 20 gal left and while still real hot I add it all to bring the extra depth to a boil to kill any bacteria and when the boil stops I draw about a gal from the draw off valve and dump it into the flue pan. In doing this the sugar is now high enough to keep it from freezing hard and it never has. I do sometimes get a thin sheet of what at first looks like ice but if I touch it I find it to be really thin slush and not solid. I do however in real cold start a little fire and then let it go back out late in the day to give a little heat to the firebrick to help. I don't really know if this is necessary. When I am in regular operation I daily use a small elec pump and use it to suck the sugarsand up and on the outlet hose which lays in another section I have a pre filter cone tied onto a fitting on the end and this really helps reduce sugarsand. This is also how I drain my flue pan at the end of the season as the 1/2" vinyl suction hose slips nicely with just a little squeeze into the bottom of the flues, it could also be used to suck sap out to await the next boil. The pump I use is about $80 at TSC , is elec and I use the foot switch from my bottler valve to turn it on and off as I control the suction and discharge hoses.

[royalmaple]

I have a sportsman and never had a problem this season with freezing and cracking anything. I just let the sap sit in there till the next boil.

Maybe got a skimming of ice on the top of the pans, but nothing froze solid. Rig was basically inside, old ice shack this year so was out of the elements but still got quite cold.

If you feel like you need to drain the pans you can run water behind the last of your sap to push it through. Then if you wanted, plug the flue pan off & syrup pan, disconnect the "U" and dump the water out, or let it drain into a bucket if it is sap. I guess when running at about 1 inch deep I have about 10-15 gallons of sap/syrup in the entire rig. If you drained like I said above, I can't imagine that you would have 5 gallons of sap or water in the flue pan, just tilt on its side on the arch and most would / should come out.

hope this helps :?

[WF MASON]

You can order the smaller dropflue pan with a flue drain or if you own one send it back to have one put on. I've seen people send back the 3' pans before and have one put on. Its not cheap,$300. bucks I believe.But worth every penny.

[ibby458]

My flue pan doesn't have a drain either. When I want to clean the pans, or shutdown for a while, I drain the evaporator thru a filter into buckets until it's less than 10% sugar. Hose it all off good, draining it onto the floor. Put a crevice tool on the shop vac, and it'll suck those flues dry in seconds.

To restart, dump your buckets back into the pans, most concentrated in the syrup pan, working backwards til the flue pan has 1", and turn on the fresh sap supply.

[Brent]

lots of tips. Thanks guys.

$ 300 is a stiff charge, but as you say, worth it.


One of the things that happens with the Half Pint is that it leaked smoke and combustion gasses all around the the arch where the pan sits. I got some insulation strip from Bascom but every time you lift the pan of you destroy it.
I don't want to keep doing that every weekend. ( next year )


Matt
As I reacall the Sportsman drop flues were all independant. Am I right in that ? That would mean a drean in every one or major surgery to join them all.


The shop vac would sure clean it up in a hurry. Just happen to have the stainless tank model. A bit of a mess to get the sap / sugar out of the hose but the pan would be empty in seconds.

[royalmaple]

The flues are all independent in the sportsman, so you would have to clean each one out individually.

There are two types of pan gasket material. 1 is about 1.00 per foot and other is about 3.00 per foot. the more expensive stuff is like braided fiberglass strands, the cheaper stuff is like a padding. If you are taking the pans on and off, you may do better with the more expensive stuff it holds up better. You may be able to dab on some of the stove adhesive that you use on the doors to adhere the rope gaskets to the stove. May hold them in place better.

Maybe others have tried this and can tell you yea or nea.