I just made a new pre-heater

[maple flats]

It was a good day to work inside, so I assembled a preheater for my sap. I have a SS tray in my hood with sides and it slopes to one end for drainage. The preheater is composed of 2 tiers of copper tubing. It starts with a 1" copper manifold with 6 copper tubes each 48" long soldered on. At the far end it has another manifold to collect the sap. From one end it rises to the upper level and repeats the same thing so the inlet on the bottom and the outlet on top are directly over each other. If I can get them to post, you will see 3 upright copper pillars soldered in place just to hold the pre-heater as a single unit. It is built with a slope, the base will rise from inlet to the other end, then the sap flows up and returns uphill again to the final manifold and the outlet that will feed the float box. In the pictures you will see 3 half inch fittings, open on the top. Once in place I will add copper tube to vent air from the heater. Where the 1" inlet and outlet tubes pass thru the hood walls, the outlet will get a Tee and a valve that will get a vinyl tube from the top of the valve back into the head tank to bleed any air or sap that may shoot up in it.
We'll see how the pics go, when I loaded them to the computer a message came up that my program was not supported since last Nov. I downloaded a new program and this is my first time trying it.13491134921349313494

The overall length is 52", the 1/2" tubes are 2" O.C. and the overall width is 17" plus the inlet and outlet tubes that will pass thru the hood wall.
Currently it is setting on my next Honeydo project, a new vanity for a half bath near our entry door.
I'll have to see what temps I get with it. My old one in a 2x6 with a hood got 170-180, I hope this does at least that well.

[maplestudent]

You're not planning on boiling in your living room, are you?

Just kidding......nice work, it looks good.

[TerryEspo]

Oh so pretty,,,,,shames what I will be using this year. Very nice.

[maplestudent]

Oh so pretty,,,,,shames what I will be using this year. Very nice.

There's no way i'd post a picture of mine. Nope, not happening.

In maple flats' pictures.....the tubing looks larger than 1/2" and 1". I was surprised when I read that (looked at the pics first)

[palmer4th]

how is your pre heater working? Im thinking about building one the same way for my 2x8

[unc23win]

Thanks for sharing I think this might be the off season I get one myself. I have one I bought used but it was plumbed the wrong way and I never got around to making it work.

[maple flats]

I get 160-175 F from the preheater, until shortly after the auto draw opens, then it drops to 115-125 F. Still pretty good, better than the 35-40 I had before.
It's my understanding copper is no longer recommended for a pre-heater. I'm going to change my feed line and pre-heater to SS when I find some old SS milk line tubing. Will need to watch lots of old farm auctions likely.

[palmer4th]

could you add a 3rd level so the sap stayed in it longer? why is the copper not recommended anymore?

[tcross]

figured i'd revive an old thread rather than start a new one. kind of looking for reassurance or advice on building a preheater. from reading Dave's post (think he has a 3x10) and some UVM research, this is what i'm thinking. i have a 30x8 evaporator with a 30x5 raised flue pan, boiling about 65 gph. i'm thinking of using 1 1/4" manifolds with either 6 runs of 1/2" pipe (6 on top, 6 on bottom) or 4 runs of 3/4" pipe (4 top, 4 bottom). is that enough pipe and is way better than the other? is it best to use a T between each pipe or can i use a hole saw and cut the hole out of the manifold and solder the pipe in? does anyone know what the manufacturers use inside a 30x8 evap? i'm sure i'll have more questions, but those are the important ones for now. Thanks!

[sandman6921]

I made one exactly like this, however I also built a tray to set under it to catch the condensate from steam hitting cold tubes. That tray basically cut off the steam and sort of defeated the purpose of the copper manifold. It definitely heated the sap without the condensate tray ( half pipes about two inches below manifold). Mine is a homemade rig and I have a chamber in the back of burner where my flue pipe exits. I had way better luck coiling 3/8 tubing atop that and eliminated the dripping condensate.