Piggyback rear pan

[partsrus1974]

How u all doing?Any of u guys ever mess around with the concept of installing a smaller pan on top of your back pan aprox a 1/4 or 1/2 the size of the rear pan,I saw one like that,I bet it realy helps increase evap rate.The thing i like about it is,it uses the steam from the rear pan for heat so its free heat.I'm sure it would take some tinkering to make it work..Anyone think its worth the effort?

[brookledge]

Many producers use them they are called "piggybacks" or "steam-a-way" pans and they do just as you said, they take the steam from the flue pan and heat the sap in the top pan. But since there is not enough heat to boil the sap forced air is used to ajitate the sap and cause it to bubble thus releasing steam and causing evaporation.
An easy way to see this is take a pan of water and heat it to say 150 degrees. If you don't touch it not much steam if any can be seen coming off the top. But if you take a spoon or something and stir it or blow into it alot of steam will be seen.
The key to making it efficient is collecting the condensate under the piggy back pan and not allowing it back into the flue pan, just as a hood with a preheater does.
Keith

[3% Solution]

Hi Parts,
Had something like your talking about made last year.
Works pretty good.
All kinds of hot water for cleaning up.
The sap feeding the flue pan is about 185 degrees.
I am going to tweek it some more this year as it really isn't where I want it yet.
Makes syrup in about half the time.
I think I'm looking at about a 50% increase in the evapoation rate.

Dave

[NedL]

How close would it have to be to the back pan. What would be too high to be effective?

[3% Solution]

Ned,
My unit sits right on the flue pan (lightly), it is suspended from the rafters.
I believe it is 20" high.
It's enclosed with six 2" pipes at the top to allow the steam and heat to go out, which keeps the heat from the flue plan in there.
Find someone that has a piggyback or steam-away and take a look at them.
There really isn't much to them, pretty basic.

Dave

[Jeff E]

Hey 3%, any pics of your rig?

I assume you need a good hood. Do you direct the steam at all or is the simply sitting in the steam chamber heating the whole piggyback.

I am thinking a normal preheater would be a lot easier to build, though there is no evaporation that happens.

[3% Solution]

Jeff,
The steam that comes off just goes up through the rafters and out the coupla, as you can see from the avatar.
We don't have a problem with steam, it's usually at about 7'.
If you send me your email address I'll send you some pics.

Dave

[NedL]

3%,

Thanks. I'm outside on a block arch. I was thinking of building a simple platform to hold a steam pan over the back pan. I though I'd put it at a slight angle to take the condensation away. Any improvements in heating the sap is big. Last year I had a 3 pan system. This year looking at 4 with the pggyback, if I can figure it out.

Ned

[3% Solution]

Ned,
If you want to heat your sap a bit run some pipe in your pan or around the stack.
I have a piece of 1/2" pipe that runs through the first section of the flue pan.
This, coupled with the sap coming out of the EEU puts sap into the pan at about 200 degrees.
Before the EEU I had 1o' of pipe up agaianst the base stack, this pipe was covered and insulated.
Hope this helps.

Dave

[partsrus1974]

thanks for the input 3% I am definatly going to play arpound with this idea, like you said there is not much to a stem away especialy for $5000:rolleyes: I was wondering if i could see some pics of your setup?what kinda drip pan you have on it?

[3% Solution]

Hey Parts,
Send me a PM with your email and I can do that!

Dave