Preheater Vent Location

[SeanD]

I'm going to try preheating my sap by running through a copper coil against the base stack. The coil will be zigzagged like a condenser on the front of the base stack and I'll hold it on with springs and a chain that I can unhook before it runs dry at the end of the night. I'll have some type of shroud or insulation on it to hold the heat against the copper - though don't know what to use, yet. The sap will drop right into the pan and I'll control the rate with a valve. I do not have a float box.

The sap will be coming down from a tank about 7' above the pan level which will be about 4' or 5' above the copper. Right now, I'm planning on 25' of 1/2" bendable copper for the preheater. I'm going to connect the copper preheater and tank with a clear plastic hose.

My question is where to vent the line. Should I put a T and vent where the hose leaves the tank or down at the beginning of the preheater where the hose meets the copper?

Thanks in advance,
Sean

[rayi]

Not sure about this type of set up but mine is vented at the top and the line runs higher than the head tank.

[Super Sapper]

If you start your copper at the bottom and let the sap rise through it, the high point should be where it dumps into your pan and should not vapor lock.

[SeanD]

I'm not sure I follow you. The preheater will be up against the base stack and the sap coming in is above it. Are you saying to have the sap enter the copper pipe at the height of the pan, travel up the copper along the stack and then come back down to enter the pan?

Sean

[Super Sapper]

feed your coil from the bottom and not the top.

[SeanD]

Ok, that is what you are saying. Sorry, it just seems counter-intuitive. So, when the hot sap leaves the coil it will be about 2' above the level of the liquid in the pan. Would piping it back down to drip into the pan defeat this effort?

[Super Sapper]

It shouldn't as long as the line going back down is big enough or you put a tee where it goes down with the op end of the tee open.