Stack temp's?

[Bucket Head]

Just out of curiosity, what are you guy's with 2x6's getting for stack temperature's?

Anyone have an idea on what the "ideal" temperature should be for a woodfired 2x6?

What would be considered too low, and what would be called excessive?

Steve

[RileySugarbush]

I run about 800F. There is no right temperature. In general, higher stack temps will increase your evaporation rate and decrease your fuel efficiency. Low stack temps will increase your fuel efficiency, but boil slower.

It is a reasonably good analogy to think of driving your car with a lead foot. You get where you are going faster, but it uses more gas.

[Jim Brown]

buckethead; We run about 850-900 with forced draft

[Justin Turco]

Hey Buckethead, I just got off the phone with leader, I asked them what temp they use when they rate an evaporator. They said that it depends on the evaporator. A longer evaporator is rated using a lower stack temp (800 or so) then a short rig like a 2x6. I told him that we run about 1200 degrees with ours. He said that was that about what they use when coming up with a gph rating for that size evaporator. When I am at 800 or so I see a pretty good boil for maybe 1/3 of the flue pan. As you can imagine, at 1200, 2/3 of the pan is really boiling hard and last third is bubbling good "here and there". For next year, I am going to close the hole, where the gasses turn down and out of the flues just a "bit" more, in the in hopes of pushing that hard boil a little closer to the back of the fluepan.

(Note: our stack temp guage has a probe on it. I guess they read a little higher than the ones without the probe.)

[WESTVIRGINIAMAPLER]

I run 1400 to 1650 on a 2x8 Leader drop flue for reference and most of the time is stays around 1600 after the arch gets warm. I would like to have a 2x10 or 2x12 to see what I could run in the stack.

[RileySugarbush]

Thats a good point, Justin. When I say we run 800°F, that is measured with a cheap magnetic thermometer. I'm sure it reads quite low. At that condition, our entire sap pan is boiling hard. I'll try and get a probe type stack thermometer installed next year.

[Justin Turco]

John, my flue pan is raised but, my "comonsense o meter" tells me that a drop flue pan does a little better job extracting heat from the fire. I would think: on a raised flue, toward the rear of the pan, the gases are beginning to flow down and away from the pan in order to exit up the stack. Not the case on a drop flue. Maybe this contributes to the boil you see at an indicated temp of 800 degrees.

But that's a debate that's older than the most of the maples we're tapping.
Heh, heh, heh...mine is still better than yours???!!!

PS. WestVirginiaMapler told us about the Candar temp guage. We like it.

[Sugarmaker]

For ref using a lost cost mag. stack thermo. we ran about 700 deg on the 3 x 10. I seen it got to 800+ but was roaring too much for my liking.
Brandon whats the info on the unit you recommend?

Chris

[mapleack]

With an external thermometer I was running 600 to 670 on our 3x10 this year. What i'd love to have is one with a probe and a remote digital readout so i could watch stack temp from the front of the arch, put it right next to the marcland control box. Has anyone seen a thermometer like that?

[maple flats]

I have not measured our stack temp, but I designed a warming cabinet that sets on the back side of the base stack, 24" wide x 30" high and 10" deep. One end lifts off and I put my glass to bottle in there. About 30 minutes later it is at 200 degrees in the oven and I need gloves to remove the glass. I hope this will eliminate molding in the bottles. I designed this cabinet with an open side to the base stack for best heat exchange. We also use this to heat our pre cooked pizza and other things. I like the way it worked out, as the head honcho used to say on The A Team, "I like it when a plan comes together!"

[markct]

my arch i am putting together has a galvanized stack and tapered stack adaptor with it, will i have problems with it burning off and such or will it just the first few times then be ok, it was on an oil arch originaly

[WESTVIRGINIAMAPLER]

I think a probe stack thermoter measures about 50% higher than magnetic thermoter if I remember correctly. Tapper(Jon) put me on to the Condar and I love it and I can read it from 10' away in front of the arch.

Here is the info and link:

3-39 FlueGard™ Thermometer
Best probe thermometer for fluepipes. Durable genuine porcelain enamel with yellow and orange zones clearly indicated on brown case -- shows temperatures in the center of the fluepipe, at a glance. Stem length 4 inches, engineered to measure accurately, for any diameter fluepipe up to 8 inches. Requires ¼ inch hole. Mounts easily with included magnet and eyelet. Readings up to 1700° Fahrenheit. Rugged steel case. Made in USA

http://www.condar.com/meters.html