Need suggestions for homebrew pre-heater

[KJamesJR]

Hey folks,

I need some suggestions for a quick and cheap home made pre heater. I’m boiling on a block arch and have a custom continuous flow pan coming in today or tomorrow.

My initial idea was to install a spigot into the side of a bread pan and place that over the holes in the cinderblock. The rising heat will warm the sap and it will drip into the pan.

This method is cheap and fast. I just need to purchase the bread pan because I have all the hardware already. I’ve seen the copper coil around the stack but I’m not sure how efficient, or safe that is.

Any ideas would be great as I’m putting taps in this weekend.

[Cjadamec]

I just setup a pump driven preheater that uses a copper coil around the stack. Its working well for me and I can set up the preheater flow to match the evaporation rate. All the parts cost me about $60. There is a thread I made that talks about it HERE. (http://mapletrader.com/community/showthread.php?31909-Poor-man-s-continuous-flow-system)

If you want to go with the bread pan route I would suggest insulating the sides of the pan either with a sheet metal wind shield or high heat insulation to prevent heat lose from the wind. You won't get too much heat coming off the blocks so you will want to create a nice sealed off area around the pan to concentrate whatever heat you get.

[KJamesJR]

I just setup a pump driven preheater that uses a copper coil around the stack. Its working well for me and I can set up the preheater flow to match the evaporation rate. All the parts cost me about $60. There is a thread I made that talks about it HERE. (http://mapletrader.com/community/showthread.php?31909-Poor-man-s-continuous-flow-system)

If you want to go with the bread pan route I would suggest insulating the sides of the pan either with a sheet metal wind shield or high heat insulation to prevent heat lose from the wind. You won't get too much heat coming off the blocks so you will want to create a nice sealed off area around the pan to concentrate whatever heat you get.

The pans shouldn't be getting much wind. A draft maybe but no gusts. I spent the summer putting together a little shanty to boil in. Walmart sells a steel bread pan for $.80. I was going to buy two of them, cut the bottom out of one, flip it upside down over the openings in the cinderblock and insert the 2nd pan into that one. I'm hoping some heat will be trapped inside the bottom pan and heat the pan containing sap.

How long would the pump run off a 12v battery?

I don't have access to power in my little shanty.

[Cjadamec]

It would really depend on the size of the battery but your average car battery should be able to power that pump for 20 hours or more if it was fully charged.

Your idea with the pans might work I'm having a hard time picturing it in my mind.

[Pibster]

I tried the copper around the pipe method. It did warm the sap slightly but you really have to be careful when the sap gets low, easy to scorch the inside of the pipe. Make sure you run water thru as the sap runs out. I would go with your other plan if I was to do it again.

[red dorakeen]

Don't know how "chiseled in stone" your block arch is but when I had a block arch and wanted to add preheating I added length to the arch to accommodate a pan to preheat sap.

I was simply scooping sap then and didn't have a divided pan. I've since bored a hole in one of my buffet pans and added a valve to use a feeder pan on my steel arch and divided pan.

I don't know how well the feeder pans that are set on top of the divided pans work, but that could be an option with an old buffet pan.

[Trapper2]

176061760717608 Maybe you could just use an assortment of kettles that you could get cheaply at Thrift stores. I used to have 5-6 setting on the edge of the arch.

[KJamesJR]

Don't know how "chiseled in stone" your block arch is but when I had a block arch and wanted to add preheating I added length to the arch to accommodate a pan to preheat sap.

I was simply scooping sap then and didn't have a divided pan. I've since bored a hole in one of my buffet pans and added a valve to use a feeder pan on my steel arch and divided pan.

I don't know how well the feeder pans that are set on top of the divided pans work, but that could be an option with an old buffet pan.

I have a divided SS evap pan. I used buffet pans last year and have two of them left. I was thinking of putting them on top of the main pan but hate the though of condensation dripping back in to the sap.

The block arch is chiseled in stone at least for the remainder of the season. It's held together with enough mortar to keep from leaking and moving about. I'll collect the data at the end of the season and upgrade as needed for next year.