Series Loop preheater

[maple flats]

I bought mine at a full line plumbing store. It was called Oneida Plumbing supply. Any plumbing store will have them, but you might not find them at the big box stores.
Don't get too hard on yourself, you are sure not the first one to make such a mistake. Just be glad you didn't get it all up and running before you found out. Most of the materials you used can be re-used. I have to run now, but I will try to give you more ideas later today.

[maple flats]

Ok, I'm back, just had to drop my truck off for snow plow repairs, a solenoid valve is bad.
Here are a few pictures of the one I made http://mapletrader.com/community/sho...new-pre-heater
I already mentioned in earlier posts what I would change or at least consider changing.
Obviously those are all from before I installed it.
If my description of it as installed is confusing, ask as many questions as necessary, I will try to help.
This is by far not the only design that will work, but you need to keep the basics in mind that I stated in my original post giving the flaws to your design. A few of those again 1. a good height above the pre-heater for the bottom of the head tank. 2. air needs a way out and that can be done most easily if each set of parallel pipes has an upward slope towards the outlet to help any air move forward. 3. a pre-heater and also a steam stack will cause lots of condensation, that needs to be kept out of the pan or it needs to be boiled away again and again.
Some things, I hope you already know: you must use lead free solder and after soldering you need to clean the flux out and off the tubing. In that old thread I posted I mentioned that cooper is not what you should use, I have not yet found where I heard or read that. My pre-heater is still made of copper.
Good luck, and don't give up. When you get a properly designed pre-heater you will reap the rewards.

[Sugarmaker]

Flackville farms,
Well not the end of the world for sure. I make mistakes all the time because I don't do the research, or just talk to others. You have put a lot of time and effort in building your preheater system.
I may be able to help like others have suggested their ideas too.
But first I have some basic questions.
Looks like a brand new sugarhouse?
I see a releaser so you may be running a lot of taps?
Looks like the front pan is pretty new.
Hood looks to be home made?
Have you boiled with this rig in this sugarhouse?
Looks like maybe a 3 x 8 or 3 x 10 rig?
Keep in mind that a preheater of the best design may get you 10% improvement in sap boiling rate per hour.
With the raised hood system your room may be completely full of steam on a good day. Assuming you already know this?
What are your expectations from the addition of the preheater??
Enough of my questions!
Ok to your questions:


1. Should preheater only be over the flue pan? mine currently extends over the front pans. Yes normally they are over the flue pan and the stem hood would be setting on the rear pan
2. How to add a vent and where in the system to add it? Does it matter on location if the tubing is level? Adding a vent in a flat system is not going to be easy to know where it might vapor lock. Most parallel flow systems have vent/s at the upper high end
3. Does a bypass double as a vent if I notice vapor lock occurring. This might work but you only know you have a problem when sap stops flowing into the float box. Might work just something else to watch all the time)
4. Should I tear it apart and build a parallel style. You might try it the way it is, sometimes you find out things are not as bad as them seem and you may get some sap temp improvement. If you dont have it I recommend a gage on the output end to see if its working.
5. What materials are safe to use for a drip tray? Aluminum, copper, SS. I would recommend stainless. I have aluminum and I would much rather have nice clean stainless. Also you may not want a drip tray. They are very common but keep a lot of steam from getting to the preheater pipes. Might want to think about V shapes under each pipe.

Probably the most difficult part of building a copper preheater of the parallel flow type is the need for manifolds on each end. I think you could salvage the majority of your copper if you decide to try a different approach.
Hope this helped just a little. Keep boiling!
Regards,
Chris

[toquin]

I run a loop preheater under a hood that sits on the back flu pan. 1/2 copper 8 runs,5' long,no vent. Puts out 180 degree sap when we get rolling. Drip tray with alum. 1/2" angle under the runs drains to a drip channel on hood. Its gravity fed and we have to keep a eye on it when head tank gets low. Works like a charm.

[Sugarmaker]

Yep there is a good example of this type of a flat system working and providing good sap temps! All is not lost!
Regards,
Chris

[flackvillefarms]

To answer a few questions of yours. It is a 2x6 setup. I have boiled with it before. Partly why i am so cautious, I don't want to ruin a good thing. I wanted a preheater last year but never got around to installing it in time.


As of today I have torn it down. I have made a setup fairly similar to the smokey lake version so that I could reuse one end of the loops. I figure if it works for a company it can work for me. I shortened my 3/4" tubes to fit over the flue pan. They are approximately 45" long when measuring manifold to elbow. As of today I will have 6 loops from the bottom manifold to the upper. On one side of the upper I have a thread in "coin vent" to bleed air, the opposite will exit to the float box. on the bottom I have a entrance for sap supply the opposite end is plugged. Currently have it set on a car hoist to try and mock up locations of pipes coming in and out of hood. I have aquirred 1/16" 1" wide "v" aluminum channel to form the drip trays under the loops. This will extend over to the drip rail of the hood and have about a 1/4" of rise 46" from drip rail. as a precautionary measure I am going to be plumbing a preheater bypass to the float box for the just in case moment should it ever occur. I will be posting pictures once I have it finished. and cleaned up.

My plan is if the coin vent ends up being a waste of time I will plumb in a line that exits the hood to a ball valve that will dribble into the flue pan to alleviate air problems.

That is where I am currently at folks. I guess that is a blessing of this weather to give me a chance to get this sorted out.


Stats
We have 200 taps on vaccum.
Surge 11 pump powered by 3hp engine. auto shut off controlled by float switch in primary moisture trap
We have 26 taps on 3/16 line
Another 20 taps on buckets
2x6 evaporator with hood. soon to be added preheater. Wood fired.
12x24 sugar house.
Polaris 6x6 big boss with 125 gallon sap trailer
2500' pump line from sap tanks to sugarhouse. Saves on wear and tear of the property.

[maple flats]

That sounds like you have made a huge gain, good work.

[maple flats]

The V's are actually a good method. Did you also address condensate falling from the steam stack?

[flackvillefarms]

Nope to the steam stack issue. Haven't got that far yet. Any tips or pics out there would be appreciated while I have it all apart and off the rig. I am skilled at fabrication so if I can see I can usually build it.

I will add this, I am a first generation maple producer. I don't have family that does it and honestly before a couple years ago I didn't have any friends that did either. Everything I have learned has been on here, youtube, or from Gavin Mackellar over at Mack's Maple Supply in Potsdam, NY. I super appreciate the help that you all have given and or posted on this and other threads. The information has helped me a great deal. I hope to contribute as I learn a thing or two along the way. My kids are sure having fun watching and my dad gets a kick out of all the projects I come up with to refine our little operation.

[Sugarmaker]

Nice work! Recovery is everything! I redid mine a couple times as I improved it!
Regards,
Chris