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cjf12
01-30-2018, 03:12 PM
First time boiling in a 3x8. Dont have ro up and running yet but have 500 gal to boil down before tonights deep freeze. I cannot seem to get above 211 degrees.
I am firing every 5 min right now with blower running on low. Did seal up under firebox where it was leaking and helped a lot but still lowere than what i expected. Also have a fair amount of smoke leaking from back at the stack where you clean the flues. Any suggestions?

cjf12
01-30-2018, 03:29 PM
Wow that changed fast. Quit typing and watched it climb to 214.5. Then i wondered if something wasnt right and saw flames in back of pan. Quicly threw 5 gal then another. I got tar. Going to let fire die and see the damage. Any help appreciated.

to100
01-30-2018, 03:32 PM
Sounds like it has reached boiling, now it will slowly rise to about 7 more degrees before its syrup.
A hydrometer will make decision for you, get it to top red line, then filter and fill.
Enjoy
There is a lot more to know but will come with time.
A ton of info here and elsewhere online.

Try to keep 3” in pan or more, I just saw your 2nd post.

BSD
01-30-2018, 06:38 PM
Try to keep 3” in pan or more, I just saw your 2nd post.

Until you learn the behavior of your pan(s) i would suggest the same, keep it deep. after dialing you can run it down a bit lower. did you sweeten the pan already? my 2.5x10 takes 300+ gallons to sweeten IIRC. not much activity until you get it sweetened.

cjf12
01-30-2018, 06:47 PM
No it wasnt sweet to begin with. I wasn't expecting much for syrup this go but figures at the least the front pan should be at boiling temp of water. Right?
Cleaned up the scorch and right now i am at about 208 degrees

BSD
01-30-2018, 07:00 PM
No it wasnt sweet to begin with. I wasn't expecting much for syrup this go but figures at the least the front pan should be at boiling temp of water. Right?
Cleaned up the scorch and right now i am at about 208 degreesdid you calibrate temp with boiling water?

Haynes Forest Products
01-30-2018, 07:08 PM
Your not giving us a lot of info. How much flu stack go you have because your complaining about smoke and combining it with your boil performance..

Do you have a raised or drop flu pan?? Is the float between the two working right?? Where did you scorch it finish pan or flu pan?

Haynes Forest Products
01-30-2018, 07:15 PM
Sometimes with a new rig you have to start by playing it safe in all your systems. All floats to run heavy, Full head tank, medium fire, blower on low, defoamer ready, wife and kids out of the shack, helpful neighbor.............wait in the truck. Then slowly dial it in.

cjf12
01-30-2018, 07:57 PM
Drop flue. Scorched in the middle of finish pan. I was trying to thin it down and think i got carried away and it shallowd up quicker than i anticipated. I also put on a spark arrestor from smokey lake in the bottom of the smoke stack. It plugged up with kreasote. I have since switched wood piles. Going better bow. Temo is about 210.3. Thinking autodraw probe is off also. I did calibrate it to water though. Just not matching up with other thermometers i have.

Haynes Forest Products
01-30-2018, 09:09 PM
I ran into the same problem with the center pan being the hottest section of the rig. I was unknowingly scorching my pan everyday. Now I would not depend on the autodraw until you get your levels right and heat under control. If your finish pan area is boiling to hard your draw off valve wont work right and the auto draw wont respond properly. You can set your draw off at a lower temp level and shut off the auto draw valve and use it as a reminder and then work into its use slowly until you Know its right. The auto draw is like your cars cruse control it will keep things steady But it wont account for a low head tank, shut valve, low sap levels or a clogged draw of valve.

markcasper
01-31-2018, 12:50 AM
If your finish pan area is boiling to hard your draw off valve wont work right and the auto draw wont respond properly.

You know, that is about the best statement I have ever read on this site.....and so true that I forget to tell others. Your right, if its boiling eratically wild, you will have trouble with the auto draw. A steady, even, laid back boil is always best.

Haynes Forest Products
01-31-2018, 12:14 PM
Thanks Mark, I forgot to mention what effect defoamer has on the situation. :o

maple flats
01-31-2018, 04:29 PM
My first question is "how deep is the sap in the pans?" At first you likely want about 2" until you learn the in's and outs. Then gradually reduce the depth to maybe 1.25". After this year you can slowly reduce the depth to 1 inch. My next question "how dry is the wood and what size is it split to?" You see smoke, on a good fire, fueled every 7 or 8 or 9 minutes you will have no smoke to see, the "smoke "out the stack will be clear and colorless. It will only smoke the first few minutes after you light the fire, and it will clear up as soon as the fire is fully going. How much wood are you adding when you fuel every 5 minutes? Likely opening the door too often and adding too little. Have your wood split about wrist size and when fueling have it ready to go in before you open the door.
Next, it will take a few hours before you get your first draw. Keep the float adjusted to hold the depth at about 2" the first few boils. If a pan got scorched you were too shallow. An extremely hot fire is not going to scorch if the depth is there. Is the evaporator level, side to side and front to back. Even a 1/4" off can affect the performance. Then just let it run, the temperature will climb as the density increases.
A 3x8 with good wood, being fed 2% sap will likely get about 55-60 GPH at 2" depth, once you get better at it and reduce the depth, you should be able to get 75-85 GPH evaporation, maybe even more, but learn first or you might need a new pan or pans.

Haynes Forest Products
01-31-2018, 04:54 PM
You also mentioned smoke out the back cleaning door. If this is a old cast iron door arch you will want to seal up the doors. It can be as easy as some strips of fire blanket. Having a blower means your not dependent on draft. BUT a weak blower on low might just barely keep up with what the fire needs. If you dont have the right amount of CFM with the blower then you need to step it up or open the draft door. Doing both is not recommended.

Sugarmaker
01-31-2018, 08:14 PM
cjf12,
Sounds like you have had a lot of new experiences! Welcome to the burned pan club. Lots of us out here.
New evaporator is just that new, they all run different. If its a lot bigger than your previous then it can boil a lot faster than you are ready for. As mentioned keep the level a little deeper. Watch it like a hawk and it normally takes a lot of sap to sweeten the pans.
I did not like the sounds of the spark arrest-or clogging up.
Hope you have a handle on it!
I have made syrup in the center partitions also.
Regards,
Chris

cjf12
02-01-2018, 04:15 AM
It was an education for sure. Had to be up at 2am for snow removal. Started boiling at 1:30pm and finished at 5am. Just in time for a shower to head back to work. I am really looking forward to getting the ro up and running.
Anyone else using a spark arrestor at the base stack? I loved the idea. Closer to heat and it wont plug up. Sounded good anyway. I admit my wood isnt perfectly dry. Its scraps from a pallet shop and not all is kilned. Think I will knock down a few dead Ash trees and try that next boil.
Overall it was a fun experience looking back. Felt like I was running a locomotive. 15 seconds from total destructuon at any point.

Haynes Forest Products
02-01-2018, 07:03 AM
cji12 excellent description of the what it feels like the first time :o

Now that your clattering down the tracks feeling like Casey Jones Just wait till you open up that head tank and watch 6-8-10% concentrate surge thru the float box and all hell breaks loose. You will feel like someone just tossed 10 sticks of dynamite into the fire box and you look down and someone has wrapped a chain around the dead man. LOOKING FORWARD TO YOUR NEW THREAD :evil::evil::evil:

cjf12
02-01-2018, 09:31 AM
:o
We will run er deep. REAL deep. Maybe even add a few buckets after the float bottoms out.

In all seriousness. Is there much difference in boiling concentrate?

maple flats
02-01-2018, 10:19 AM
Yes, far different, but once you figure out sap, concentrate will be easier and lots faster. For depth, just set the float to regulate the depth, the bucket of sap is just for emergencies.
As far as a spark arrester, if you have one at all, put it at the top not the bottom of the stack. If sometime in the future you add air over fire (AOF) the sparks will no longer be an issue, everything will burn up under the pans.
Before I built my AOF I had sparks and flames at the top of the stack, however the flames did not travel from the firebox all the way up, those flames were from hot wood gasses re-igniting as they got the oxygen needed. All that comes out now, with AOF is invisable and no sparks.

blissville maples
02-01-2018, 12:02 PM
I have been this blog and have noticed a couple people mention making syrup in the middle compartments. I am not sure if you are adding defoamer to the middle compartments to reduce the foam however if you do this to control foam you will generally make syrup in those compartments as the syrup will typically follow the de foamer instead you will want to try adding more defoamer to your back pan. If you need to add defoamer to your front pan on a regular basis you're not using enough in the back pan

Haynes Forest Products
02-01-2018, 01:11 PM
I'm going to 20% and my 3x10 was going crazy so I cook on low fire because I couldn't control the heat. The flame was blasting off the arch transition making the center pan the hottest area. Then I was making syrup in the center pan but my auto draw off probe was in the last channel of the end pan. Things just got to crazy with the draw off and syrup flowing thru the pans not keeping up. I now reversed my flow so sweet/near syrup travels to the end finish pan and then to the center pan now things are ripping alone without scorching. My probe and draw off in now from the center channel.

cjf12
02-01-2018, 02:54 PM
Confused. Im still new to evaporating so excuse my ignorance. Curious how do you draw out of center of pan? Do you have plumbing for each section to draw off? I can reverse flow but not much else.

Haynes Forest Products
02-01-2018, 04:14 PM
OK well this might be like describing a kiss concert if you have never seen one.
I have a 3 pan set up a flue pan and 2 finish pans with 1 divide each. So my plumbing was out of the flue pan into the first finish thru that then into the second finish and out the draw off.
I had a bunch of milk house plumbing and fittings. So I came out of the flue pan and went to where my draw of was. Then I put the draw off where the plumbing from the flue used to be.
Now I dont have the new style reverable pans with the cross over plumbing and valves. My is a 16 year old set up that to revers you changes out the float boxes and draw off and did it that way YIKES. I just run my rig till its nitered over and switch out my spare finish pan and get back to cooking. I do a complete finish pan clean out every time I cook.

blissville maples
02-01-2018, 06:11 PM
Confused. Im still new to evaporating so excuse my ignorance. Curious how do you draw out of center of pan? Do you have plumbing for each section to draw off? I can reverse flow but not much else.

You can't, to avoid this do not add defoamer to the center of the pan. Of course this is the hottest area of the pan, and can foam first, but with the properly maintained gradiant by using enough defoamer in the back pan the syrup should always be near the drawoff. Also try a drop of defoamer near the draw off valve and this should pull the syrup that way. I've yet to understand this principal of physics but syrup follows the defoamer

Haynes Forest Products
02-01-2018, 07:12 PM
I used to have an old English tin 3 pan set of pans from the 40's and it had the draw off in the center pan. It was a very unique set of pans. I replumbed my pans to draw from the hottest section.

Now remember High pressure moves to low pressure every time so I believe when you add defoamer your lowering the level of the liquid by breaking up the foam/surface tension. You lower the level and in rushes the higher liquid.

blissville maples
02-03-2018, 06:40 AM
I used to have an old English tin 3 pan set of pans from the 40's and it had the draw off in the center pan. It was a very unique set of pans. I replumbed my pans to draw from the hottest section.

Now remember High pressure moves to low pressure every time so I believe when you add defoamer your lowering the level of the liquid by breaking up the foam/surface tension. You lower the level and in rushes the higher liquid.

Your deffinantly on the right track with the physics, it's something like you said it breaks the "tension" and disperses the heat by pressure differences. That's as far as I can understand it, logic and common sense does not apply to this particular scenario!!!