I tried it ,helped a little but heard from someone else who had trouble with it. If it gets too hot it could cause a vapor lock and sap will not flow. Good luck
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I tried it ,helped a little but heard from someone else who had trouble with it. If it gets too hot it could cause a vapor lock and sap will not flow. Good luck
I did that with my half pint it works well. I had it plumbed with a brass screw valve at the end so i control rate. I wrapped the coil just a little loose and that seemed to help it from getting to hot. I would swing it to a pot sometimes when i did not want to add cold sap but at the same time you cant stop flow or it will boil in the pipe. I usually had two copper lines one cold line not going around stovepipe and one that did...
Here is a picture from my old evaporator. 2 runs of 25' each with small valves at the end to control drip into the pan. Would boil sap if flow was slowed too much. Worked great!
I used this method to great effect; on my old barrel stove I used 1/4" copper tubing around the 6" flue pipe, wrapped around 3 or 4 times and then wrapped the coil with fiberglass insulation held in place with steel wire. You have to boil at a fast enough rate to keep the sap moving through the coil but it can be done. Sap came out of the tubing too hot to touch. You just have to experiment with number of times going around the flue and how fast you feed the pan.
What happens when you get to the end of the sap supply? I don't imagine letting the coil go dry is a good idea? I've often thought this method of preheating, but that question always stopped me.
once you have run out of sap, just open the valve at both ends to allow air movement and the copper will be fine
I guess I wasn't really worried about the copper itself, but more of the sap residue on the inside of the pipe burning to a crisp. Maybe this isn't a concern.Quote:
Originally Posted by sniperdodo
The sap residue will burn to a crisp. The next boil, get the coil hot again and then let the cold sap run through. It will "hiss and spit like a pissed viper" (credit to who for this famous qoute???) and then clear out and work fine. Catch the spittins' in a pot so it doesn't land in the pan. You're back in business!
Look at my pics in my avatar that's how i do mine. 100 feet of copper.
I have use it twice, works good. Any rise of temp of sap is good
because it won't steal energy from your evap.
Guys,
This discussion made me decide to try this. I have some 3/8" soft copper lying around. But: how do you wrap the copper tightly around the stack? Any hints for how to do this easily without crimping the copper?
Chris