Preheater box idea

[SevenCreeksSap]

I picked up a stainless box at an auction for 10 bucks. It has a lot of what looks like calcium caked in it, so I'm not sure what it was, maybe something to do with milking. It has 1 threaded fitting at the bottom and a removable lid. size is approx 14 x 8 in x 14 height. probably holds about 2 gallons of liquid. I was thinking of using it for a preheater, attached to my stack base maybe for heat, with the cold sap coming from my head tank to this, then into the pan. OK, can you visualize it?

I'm currently boiling at about 10-12 gph, but going to add a blower and insulating blanket so expecting 15-20, maybe more on the 2x8 pans. I dont have a good hood setup yet and may not be able to this year. My sap control into the pans is a manual valve at the pan inlet. I'm kind of limited on how to set this box up due to space in the sugarhouse.

I'm wondering if the sap will have time to warm up if I just use the stainless box with the sap going into it in bulk, with the evap rate I'm hoping for. If I can do it, would it be a better idea to run copper tubing back and forth all inside the stainless box, and fill the box with water that will heat up and remain hot on the stack base. would the smaller amount of sap in the copper pipes heat up faster and work better with the increased flow?

I'm just looking for something not to kill the boil.

[RileySugarbush]

Both of the configurations you suggest, Sap in the pan or water with sap running through a tube would work about the same.

But those kind of preheaters really don't work very well. The best bet is to use copper tubing with the sap running through it over the pan, best in a hood, and definitely with a drip tray. Many people run sap through copper wrapped around the stack which can really heat up, but has some problems, and even some hazards.