Pre Heater

[adk1]

What does it actually mean to have an evaporator with a pre heater? Is it significant to have? What would be the difference having an evaporator without one?

[NH Maplemaker]

adk1,It could mean time and money! If you have a hood on your back pan that helps you get reid of the steam. You would place a series of copper pipes (size would depend on size of your evaporater) from front to back of the rear pan. They would be placed were the steam would pre heat the cold sap before it enters your boiling sap.(Killing your boil) My pre heater runs around 200/210 degrees! Look at Westvirginiamapler pics under preheater.
Hope this helps!

NH. Maplemaker

[OGDENS SUGAR BUSH]

pre heater heats the sap before it goes into your flue pan. very handy to have. it increases the boil.

RICH

[WESTVIRGINIAMAPLER]

I have some pics of mine on the weblink in my signature if it helps you understand a little better.

[partsrus1974]

Hey WESTVIRGINIAMAPLER hows it going?Did you make that pre heater?i was wondering how it works with it hooked all together,verses being made to flow through all the tubeing?

[Clan Delaney]

The name of this game is EFFICIENCY! Regardless of what you're burning (wood, oil, or, ugh, propane [been there, done that]) you want to try and make that heat do as much work for you as possible. Flue pans for example increase the surface area that the flames can come in contact with, which uses more of the generated heat and increases the boil. Most pre-heaters are designed to reclaim the heat from the steam that's created when you boil.

Here's one of WESTVIRGINIAMAPLER's pics that were mentioned above:

http://i203.photobucket.com/albums/aa160/wvmapler/Preheater/4ffc.jpg

The hood sits on top of the back pan and collects the steam. Cold sap travels through the copper pipe, collecting heat from the steam as it goes, eventually exiting into the back of the pan. Steam that condenses on the cold pipes falls to the tray below (so as not to end up back in your evaporator pan!) and is piped out of the hood. I hear it's a great source of hot water for cleaning your equipment.

But that's the Cadillac of pre-heaters. I believe the Leader Half-Pint evaporator simply uses a smaller pan that sits toward the back of your evap pan. Fill it with cold sap and the steam heats it, just not as efficiently as a steam hood would. Last couple of years, I was batch boiling in pots on top of propane cookers. I just used some of the wife's cake pans, balanced them precariously on top of the pots and put my cold sap in there. Every 20 minutes I'd go out to the shack, dump the now 150 degree sap in the pot, and repeat. I probably had some issues with sap condensing on the bottom of the cold pan and dripping back into the pot, but regardless, it was better than adding cold sap to the boil. I know I've seen pics from someone here on the Trader who's pre-heater is (or was) some copper tubing wrapped a few times around his exhaust stack.

My goal is to find a way to use so much of the heat from my arch that I just get a cool breeze coming out of my stack!

[WESTVIRGINIAMAPLER]

I made it and it works great. Made it out of all 3/4" thin wall copper pipe and 3/4" copper fittings from Lowes. Syrup goes in the low end which is the end that has the brass valve on it and flows aprox 4" uphill as the length of the preheater is 52" if my mind serves me correctly. It is a parallel flow preheater and not a continuous flow. At the end of the boil, I open the brass valve on the low end and drain it for the night and go home. I get sap anywhere from 140 to 200 degrees just depending on how much I damper the stack.

I built is 3 or 4 years ago and it cost me $ 116 at the time. It may be more now, but copper is coming down a lot. On the outside that I don't have pics of, I have two 3/4" brass quick connects that work great to quickly connect or unconnect it. They were abour $ 6+ @ at Lowes and are soldered on also and eliminated the hose connections on the outside of the hood that are in the the picture above that Clan posted.

FYI, a 3/4 x 1.25 copper reducer works great as the outside diamter of a 1.25" copper fitting is same as Inside diamter of 1.5" tubing or pipe.

[WESTVIRGINIAMAPLER]

More info on the picture above that Clan posted, there are 5 pipes that are level with each other and if you look, the 4th pipe from the left is above the others. This is the inlet pipe and it runs into the low end manifold of the preheater and the head pressure forces the flow back uphill which allows it to heat evenly. There are other pics on my weblink that show more detail when the preheater is laying home in my garage before I installed it into the hood. I am not a plumber and I probably built it in 1 to 2 hours as I knew what I wanted to do when I started.

[Grade "A"]

I made mine out of 1.25" copper, about 16' inside my hood. It gets hot enough the you can't touch the outlet pipe. I think you need a hood to get the pre-heater to work good.

[WESTVIRGINIAMAPLER]

With manifolds and incoming pipe, I guess there is aprox 30' of 3/4" copper inside my hood.

[nymapleguy607]

On the topic of preheaters has anyone seen the way that some of the companies are making the preheaters. I looked at one built by leader and Patrick Phaneuff and the preheater pipes run horizonally in the hood the sap comes in at the top and runs down towards the front of the pan and then loops back would that be as effective as building one with some slope and bringing sap in at the bottom
Just a thought Jeff

[peacemaker]

wvm where are you catching the condesate

[adk1]

ok, so another question, do basically all commercial evaporators like the Hobby laPierre 19"x36" pan evaporator have automatic movement of the sap to syrup so that you do not have to move it yourself??

[Jeff E]

Only if there are partitions in the pan(s) for the sap to flow from inlet to outlet. This gets the 'gradient' of concentration going.

When I used to cook on a 2x4 flat pan it was simply dump in sap all day and empty at the end of the day. No flow or intermitant draw offs of syrup.

[peacemaker]

and u dont need float boxes to do that just the sections and valves the evap i am selling is like that there is a valve between the pans and one on the end of the fill tube i set the in too what i am boiling off that keeps the level at about one inch to 3/4 ..and i can continous draw at a rate of 1/2 a hour or so ...

[RileySugarbush]

Exactly as Jeff says. Think of the partitions as making the pan act like it is many times longer than it is wide. Sap in at one end and syrup out at the other, with the ends so distant from one another that they cannot mix.

[Haynes Forest Products]

If you have a single pan you have a batch evaporator. if you have 2 compartments then the syrup will move by itself......but the sections should be flue pan 2/3rds total size with the syrup pan smaller. The more sections you have the better control of the total process.

[adk1]

Well, that seals the deal then, I am definatly purchasing a commercial evaporator. Now, the question is, Leader or LaPierre......

[adk1]

Well, that seals the deal then, I am definatly purchasing a commercial evaporator. Now, the question is, Leader or LaPierre......