Advice

[bix]

I just purchased a new evaporator, it is a 2x8 drop flue, the syrup pan is 2x3 and the evaporator pan is 2x5. This has hoods on both pans. How many gallons of sap will I be able to boil off?

[Mark-NH]

I would think you could process about 60 gallons + an hour with that limited information. This is providing this is a fairly modern rig with 7" flues. Easiest, and least expensive way to increase that number is by adding a blower to the fire box.

[3rdgen.maple]

Are you asking how many gallons an hour or how many gallons total? I would guess 50 to 60 an hour and if you mean the season I would guess it would depend on how much sap you get and how much time you have:)

[vermaple]

It depends greatly on what you have. Preheater,Forced Draft,etc. With hoods, I would guess that you have a preheater, Without the hoods won't do much if anything except get rid of the steam. That said without preheater about 40+-. With preheater about 45-50, with forced draft 45-50, with both 50-60 depending on quality of wood and firing. With oil about the same without the firing variable

[parkerfamilymaple]

a good rule of thumb for a normal evaperator is three gallons per square foot

[3rdgen.maple]

Martin I have no doors or vents on the ends. Big reason why is the nasty weather comes from my west and the doors face north and south so I wanted the end enclosed to keep the rain out. So I just have doors on the length of the coupla. Did my explanation on how I made the doors open make sense?

[PerryW]

I agree w/ Mark. About 60 GPH assuming 7" flues.

[WESTVIRGINIAMAPLER]

I can't see 60+ out of a stock 2x8 with a 5' flue pan. I have a 2x8 drop flue with a 5' flue pan and 7.5" flues and it would run 35 gph stock. With a preheater, inferno arch and modifications to the inferno arch, I get 60 to 65 gph. These numbers include startup and shutdown. I think a lot of people forget to include startup and shutdown time in there gph #'s and just state the best gph #'s during a boil.

[3rdgen.maple]

Hmmmmmmm. Interesting. I am just curious how many people calculate their gph from start to finish or from when the gate is opened till the tank is empty. Here is a thought, If one manufactures claim on gph is when the sap starts to boil and and another manufactures claim is from the light of the match who might get the most sales? I bet that they all go buy when it starts to boil. I know in the industry I am in when they claim a printing press can print 13000 sheets an hour that number is when the first good sheet comes off the press, it does not include make ready time. Same for a copier claiming 50 sheets an hour. Xerox does not include the time from when the thing is turned on. I now when I have to figure out how long it will take me to drive to a customer shop so I can bill them accordingly I don't calculate in a shower, breakfast or getting dressed. Im not saying that Westvirginiamapler is wrong by any means Im just thinking about other industry standards and such and wonder why we would calculate boil rates from the light of the match.

[Fred Henderson]

3rdGen ,
You make a good point. With wood it takes me a good hour to get things really warmed up. But I am boiling with in 10 minutes. How ever if I were to use oil I would boil sooner and faster. So I look at mine and when I see a 500 drg stack temp I know that is about as high as I want it to get and at that temp I will evap 90 gals an hour.

[DrTimPerkins]

3rdGen ,
You make a good point. With wood it takes me a good hour to get things really warmed up. But I am boiling with in 10 minutes. How ever if I were to use oil I would boil sooner and faster. So I look at mine and when I see a 500 drg stack temp I know that is about as high as I want it to get and at that temp I will evap 90 gals an hour.

Almost all of these types of measurements are done when the system is in "steady-state" or equilibrium conditions, meaning the arch and pans are hot and things are boiling at their peak rate. If you're boiling sap (instead of water), it would be after the evaporator has actually started making syrup and you've had at least one draw off. The first 30-60 min even an oil-fired evaporator will have a slightly lower evaporation rate until everything is completely hot. With wood and a bricked arch it can be even longer than that.

The other complicating factor -- if you're boiling sap -- is how much syrup is being drawn off. If you're producing for example 2-3 gallons of syrup per hr, you need to subtract that amount from the total amount of sap you've gone through (that amount wasn't evaporated, it is syrup).

Tim P.

[Fred Henderson]

Tim, Thanks for the head up on this. I do know that the guy that I have out in the woods gathering better be back in 1 hour with a 125 gal laod if all I had was 100 gals to start with or I am shutting down.

[3rdgen.maple]

Dr. Perkins thanks for the info. I never considered you had to subtract the amount of syrup that is drawn off. Seems so obvious now that you mention it. We just all now lost a few gph's I think.

[Fred Henderson]

3rdgen, After all we are syrup makers not researcher.

[WF MASON]

I do believe it takes 2 hours plus for a wood fired evaporator to get the brick and arch heated to get the full evaporation possible. The syrup not evaporating never came to mind.
Its must say having Dr.Perkins join in on 'the trader' brings things to another level, I certainly appreciate his input.

[stoweski]

QUOTE parkerfamilymaple:
a good rule of thumb for a normal evaperator is three gallons per square foot
__________________
18000 taps
6x16 revalution
QUOTE


An off topic question... exactly WHO taps 18,000 taps? Man, your arms must be tired! :o

[Amber Gold]

10-4 on that. Tim has been very informative.

[KenWP]

QUOTE parkerfamilymaple:
a good rule of thumb for a normal evaperator is three gallons per square foot
__________________
18000 taps
6x16 revalution
QUOTE


An off topic question... exactly WHO taps 18,000 taps? Man, your arms must be tired! :o

Trying to figure out how to get 3 gallons a sguare foot. The going rate here seems to be 1.5 gallons a square foot at the hardest boil you can get. I have measured the boil rate countless times and that all I can get. Granted my gallons are some what bigger then yours but still. I am wondering if thats with a flue type pan and if it is will that increase my boil rate to have some kind of drop or raised flues on the pan.

[3rdgen.maple]

Ken it is all about surface area. Flues give you more of this without taking up the whole sugarhouse. I do believe though that you will get somewhat of an increase with the flues in the fire instead of above it. As far as the numbers in relation to surface area I have never sat down and figured it out but 3 gph per square foot seems a little high to me as well.

[Russell Lampron]

With proper firing I have exceeded the 3 gals per sq foot many times. Raised or dropped flues doesn't seem to make much of a difference. The flames are directed up into the raised flues with a properly bricked arch. On a 2x6 that comes out to about 35.25 gals per hour with raw sap.

[Parker]

There have been times Marvin has done 300 gallons an hour with perfect conditions, most of the time we click off 250 an hour.....5x16=80x3=240,,flat hood with a old grimm preheater.....BUT I AM GOING TO KEEEP ADDING MORE BLOWERS TILL I HIT 350/hour all the time :)

[Bradenfish]

I can get 80 gph tops on my 3x10 drop flue Darveau . My cousin got 80 gph on his 3x8 raised flue Dallaire. I think different brands of evaporators can give you different results. Just my 2 cents

[maple flats]

I only get about 2.4-2.5 gal/ sq ft with my set up. I have a 3x2 syrup pan and a 3x6 raised flue pan. If I boil any faster I loose sweets out between the pans and the hoods. I will have to re design the hood to help this before I can boil any faster. I do know it is a poor mating between the two but I must need help to design a better way.

[dschultz]

I have a 4x14 forced air and get 300 gph.And when things are going really good I get 350 to 400

[3rdgen.maple]

With proper firing I have exceeded the 3 gals per sq foot many times. Raised or dropped flues doesn't seem to make much of a difference. The flames are directed up into the raised flues with a properly bricked arch. On a 2x6 that comes out to about 35.25 gals per hour with raw sap.

Russell here is the thing. 2 x 6 =12 35.25 divided by 12 is close enough to 3 But the square footage on your pan is more than 12. You have to add the the flue measurements in there as well. So 3 gallons per hour is still high in my book. I get on an average 35 gph and on real good days I have seen 40.
If I remenber correctly square footage on my flue pan is almost 36 square foot plus the syrup pan put me around 40 square feet of surface area.

[WESTVIRGINIAMAPLER]

The main difference in evap rates is the experience of the person firing the evaporator and the quality of the wood, not so much the difference in pans by difference manufactures. Dallaire has a high efficiency flue pan that adds about 20% more flues, so this would increase evap rate.

My dealer in Pa is Amish and a few of the members on here know him and he went to a Max flue pan and it increased his evap rate about 50% and he has a stanard wood fired arch unless he changed it in the last year or two which I doubt, but I forgot to ask him.

Leader is coming out with a new higher efficiency arch in the next year or two, be interesting to see how it performs at is appears it is going to be about 1/2 the price of the Force 5.

[Russell Lampron]

3rdgen,

I think the rule of thumb that parkerfamilymaple was referring to just goes by the square footage of the evaporator without taking the surface area of the flues into consideration. If you look at the chart in the Leader catalog the evaporation rates pretty much match the formula. In the real world it is pretty much true too.

[3rdgen.maple]

Well not sure about the real world comment but if he was referencing the size of the evaporator than I agree 3 would be close.

[red maples]

on average your probably right 3 gallons per sq. foot is a pretty good estimate. I thnk this is most important when you are on the edge of how much sap you have vs how much time you have to boil and do you need to a bigger rig, yes we all want to get the most out of our Evap. with the least amount of wood, time etc... what it really boils down to (no pun intended) is that we love this hobby and weather it is a hobby or a serious part of your yearly income. and we still want the most syrup for time and money spent.

but it will be different for the type of pan you have right? flat vs. riased vs drop flues it all come down to surface area. and if you want to get really scientific type of wood, firebox width and height. And don't forget about the operator with the screw loose for maple:D .