Need More GPH

[Bradenfish]

I have a 3x10 Drop-flue Darveau. I was running 2'' and getting 50 gph. I was told to lower my depth so i went to 1 1/2'' and got 60 gph. I'm burning good dry white ash and have good draft. stack temps up to 550. If i go much lower than that i have a terrible time with foam when i'm drawing off. (starts out nice full stream then starts getting weaker and weaker, temp gets way too high, frantically scoop sap into syrup pan) Heard of several people that are getting a lot of foam this year. I do need to put gasket under my pans- its back ordered. Any ideas? Thanks

[sapman]

Bradenfish,
I used to get about 60gph out of my Leader 30X8 drop flue. When it was completely stock, I sometimes ran as low as 3/4"-1". Things can go bad fast at that depth, but I think can be done. But I don't think that would gain you enough speed to really notice that much. Try calling the manufacturer and see what he says. I'd say adding forced-draft would be a good enhancement to start with, if you're so inclined.

Good luck,
Tim

[Haynes Forest Products]

you should be doing alot more than 60GPH. When you draw off GO SLOW if your depleating the finished syrup in the pans small steady stream. I dont think you have foam in the finish pan its thick syrup thats on the verg of going candy on you. As syrup thickens the surface tension increases and it holds the air under the surface causing a foam effect.
Do you have a preheater? I think you need more heat under those pans 550 stack temp with wood seems low. In a pinch you can use fiberglass as arch gasket.

[benchmark]

Whats the length of your stack? I know you said you have a good draft but they recommend the stack being 2x the length of your evaporator or more to get the best draft. Should be getting way more then 550* out of your stack with wood.
Just a thought.

[Jerome]

sorry to get slightly off topic where do you measure stack temp?

[maple flats]

I think it sounds like you are drawing too fast in batches. Try drawing steady, in a fine stream and monitor the temp/density. I had similar problems but 4 years ago I started doing constant draw and i no longer had that problem. My rig is 3x8 but I started it with a 2x6. The draw is very slow but steady, and I often need to stop to wait or sometimes speed up but I am always trying for steady draw. The bigger the rig and the use of an RO would both make steady easier. I started last year going slightly heavier than syrup to draw and then thin in the canner as needed, by adding near syrup from the evaporator. For this I do draw faster off the pans but still not full open valve, I draw a little, filter it into the canner, stir, test and add again if needed.

[Mark-NH]

Forced draft is the easiest and cheapest way to up performance imo. I would not run a wood fired evaporator without it. Then you should be able to run a little deeper and not have to be on the edge.

[WESTVIRGINIAMAPLER]

Forced draft and airtight is definitely the way to go for more gph. I went from 35 gph stock on a 2x8 to 65 gph changing it to an inferno arch and a hood and preheater. I would guess the preheater gave me about 5gph and the inferno arch and big blower about 30 gph.