Temp Drop

[fruitguy]

My second year and have moved to a 2x3 divided pan. Trying to finish off my first syrup and it seems like I am getting a huge drop off on temp. Pan comes to a boil and then I lose temp. Not sure if I am doing something wrong.

Any input would help.

Thanks
James

[ecolbeck]

Does the drop in temp coincide with anything (such as reloading the firebox)?

[fruitguy]

No, I am actually burning over a propane burner. Last night I even tried bringing the level of the pan down to an inch from 2 inches. The thermometer by the draw off gets up to boil then later drops. I can't figure it out. I want to get it as close as possible before I draw it off and finish it, but for some reason the temp is dropping by the draw off valve.

[steve J]

Is your pan perfectly level?

[bowhunter]

I have a 1/2 pint which is a little smaller than a 2x3. It is really hard to finish syrup on it and what usually happens as you get to almost syrup the syrup side starts to foam and then you get a lot of back mixing with unfinished syrup and the temperature drops on the syrup end because the boiling point is lower. I run an RO and only have about an inch in the pan. I finish off the pan that way but sometimes I have the same problem you describe and have to slowly let the level drop a little to get back to syrup. I agree with others make sure your pan is level.

[fruitguy]

My pan was level to start, I will check it again when I get home tonight.

[ecolbeck]

Is the application of heat even across the bottom of the pan? I wonder if the idea that mixing of sap of various densities (and temps) is what's occurring.

[Sugarmaker]

I would check if the thermometer tip is in the syrup when boiling? At 1 inch deep it may be just bubbles around the thermometer?
Regards,
Chris

[fruitguy]

So I think I figured it out. I think I have two things going on.
1 I let the level get too low and thermometer was not reading correctly
2 I am used to a smaller flat pan and based on what I am reading I need to run a lot more sap through the pan. Once I get a 100 or so gallons run threw I should start being able to pull off some near syrup.

At least that is my theory for today

[maple flats]

It can be hard to draw syrup off a 2x3, but I used to do it sometimes. At other times I drew off maybe 1-1.5 gal from the draw off valve while I added at about the same speed on the other side at the same end (mine had 4 channels, some only have 2.) Just keep the fire going as hot as it will burn, make sure you maintain the depth in the pan and it will happen.
Even on my 3x8 boiling 10-12% concentrate it seems to take longer than I would have guessed to draw off finished syrup, but once it starts , just keep going. I used to attempt a constant draw once I got to syrup. On my 2x3 I at times got a draw of about 12-15 minutes (about pencil lead size stream) before I lost temperature. Much more often I only got a draw of 2-3 minutes. (still the same size flow). As I grew to a 2x6 I actually got an occasional draw of 30 minutes, but most were in the 10-15 minute range.
It seems the hardest part is fueling a wood fire and being able to maintain a draw, on propane it might be easier, I'm not sure, I never boiled on propane. Anyway, it seemed to me that attaining a long duration draw helped understand exactly what was happening in the pan.