getting red hot

[deere_jennings]

having trouble with base stack getting red hot when boiling hard. 3x8 raised flue pan 12" stack 14'of stack with air under fire ramp under back pan with vermiculite. thanks for the help

[bowtie]

sounds like you need to turn your blower down a little, had this problem with my 2x4 before. if it doesnt not melt your stack it really isnt a problem except you are wasting a lot of heat through stack. also you really need at least 16' of stack, double your evaporator lenght generally.

[motowbrowne]

Sounds like it's working to me. If you want less stack temp, you could reduce the air coming from the blower but you'll probably also lose some evaporation rate.

Of course, the best solution would be to stretch your arch into a 3x12 to use the extra heat, but that's probably an expensive option.

[Sugarmaker]

Sounds like your doing things right. maybe stretch your firing time a couple minutes. Load a little less wood each firing?
We had issues like that and were just firing too much too often. We also added a outer layer to the base stack with a air gap and venting and this made the stack more tolerable to be around and safer!
yea they said that wouldn't work either!
Make sure your insulation under the flues (sand) is within a 1/2 inch of the bottom of the flues. You want that rear pan to be sucking as much heat as possible out of the fire and putting it into the sap.
What is the shape of your ramp? Is it sized right and up within 1/2 inch of the bottom of the flues? Area for ramp down should be about the same area as your base stack. I think the ramp should block about 30% of the rear pan area????
How is the rear pan boiling? You should have sap jumping out of the rear pan?

Regards,
Chris