first time boiling with a blower..???

[foursapssyrup]

today was our first time boiling with a squirrel cage blower, not sure of the CFM, but it blows good. The evap rate was great, somewhere around 30-32 GPH.

our draws were a lot shorter than without the blower, and we lost most of our gradient. the rear pan is almost the same color as the front. typically you can see a gradient difference across the dividers in the pan.

the question is, can the rear pan evap at such a great rate, it mixes the front back in it from time to time? our draws were short, less than 1/2 gal, with a rapid drop in temp nearing the end, to 3 or 4 degrees below syrup. pre-blower we would draw at the same rate for much longer, almost a continuous flow with only a small drop in temp at the end of the draw, maybe 1 degree.

i guess i just cant figure out why we weren't getting more syrup from this boil, than we would a typical boil without the blower. seems there is a lot of syrup in our pans.

[CampHamp]

I have a raised flue, so it's a one way street between pans. I only seem to lose gradient within the syrup pan, though, if I draw off too fast or if my fire gets too low.

With the blower, are you waiting too long to refuel and it's cooling the front pan? Are you boiling the heck out of the middle channel and drawing fast to get that syrup to the spout?

[Super Sapper]

You may be blowing the heat past the syrup pan. Do you have a hard boil in your syrup pan? You may be doing all your evaporation in the flu pan and not enough in the syrup pan to get it to syrup before you have syrup in the flue pan. I would restrict some of the air from the intake of the blower and see if it helps.

[SmellsLikeSyrupNH]

This is what I did to my squirrel cage blower to reduce my air flow, it was blowing TOO HARD and too hot for me....
9379

Im sure my evaporator is a different style than yours, but I found that I was getting the rear pan to boil too hot too fast, so reducing the air intake helped me get to where I wanted.

[bowtie]

i have same issue with my rig, boils jump out of flue pan area and front syrup part only boils hard sometimes. I have smoky lake 2x4 hybrid pan and it takes a lot of boiling set gradient and you quickly lose it for a while after small draw offs. boil rate is fine but all I have made is dark amber this year to what I believe is the fast that it takes so long to set gradient, pretty much batch boiling. I pretty much have made my mind up to not get a drop flue evaporator next year, I thought they were better but seem like a pain in the butt. I definitely have more syrup in the pan than I can draw off. as to the blower do you have a rheostat to control the speed?

[wiam]

Damper is better for the motor than a rheostat

[foursapssyrup]

we are firing a little more often than we were pre-blower, so the fire is not dieing out on us. stack temps remain pretty constant. our draws are slow, a little faster than a trickle, and pre-blower we draw off a gal or so before shutting the draw off valve, and had a very short recovery time to the next draw.

our syrup pan is in a hard boil at all times the blower is running, (we do have more foam in the syrup pan than we did pre-blower, and have tried to remedy with a drop or two of defoamer with no success) our back pan has boiling geysers almost the full length of the drop flues.

i have a pipe fitted to the blower shooting the air up to the bottom of the fire. it is on a rheostat, and i tried a few different settings to see where the boil was happiest, and it seemed to like almost full bore with no other air coming into the fire except via the blower.

what we drew off yesterday was a dark amber, while what we drew off sat. was a very light amber. the sugar is spending too much time in the pans, and i pretty much have given up on using the blower again. Our goal is light syrup, and the thoughts were the blower would help us boil faster, thus making a better grade syrup.

[maple flats]

You likely have some other issue. The faster the sap becomes syrup the lighter it will be. Maybe the sap turned, maybe you had a near emergency, too low or sugar sand in a hotter spot. If everything is done right the blower will help not hinder.

[adk1]

Which way is your blower "blowing"? I mounted mine so that it blows toward the firedoor, that way it circulates the heat up under the syrup pan and out through the flues. I would think that if the blower is blowing straight back then you could affect the boil in your syrup pan area

[TerryEspo]

I agree with adk1. I seems to me if the blower is in the door blowing towards the stack it would not be as efficient as if blowing toward the door. Much more turbulence going on when the blowing is pointed toward door and under the grate.

Just seems like what natural convection would do, just with more speed, lol.

I hope you get it figured out, good luck.

[maple flats]

Mine also blows in from the back, but mine blows into a 4" round stack type pipe. Then I have it capped on the end, 6" back from the front. I have 3 rows of 1/4" holes spaced about 4" apart, 1 row top center and 1ea facing the outer grate. It works well, but mine is tied to my high pressure blower for my AOF and each is valved to regulate. The under air is open about 25% and the over air is open about 65% each on 3" ball valves.

[foursapssyrup]

the blower is coming in from the front, but set up just like maple flats. with a 4 inch duct, capped and 3/4" holes so the air blows up into the bottom of the fire, not towards the back of the evaporator.

we run 1 " level front and back pans. I still can't figure out what was going on. upon cleaning out the front pan, we found a LOT of sugar sand. we thought we burnt the pans, (didnt though) we couldn't see bottom and the syrup was that dark. maybe that had something to do with it.

what still has me guessing though is why would the syrup have such a rapid drop in temp, from 2* past syrup to 4* below syrup in the matter of a minute. then a long time of boiling to recover from it. it's like our syrup knew it was being drawn off and said "no way, i'm going back where i came from, and away from that opening!!" never had that happen before.

[adk1]

Yeah that does sound strange

[harrison6jd]

hey guys, im still figuring out my new setup over here. you saw my fan is on a dimmer switch (which i know is bad for the motor) and i can see the change in boil when i have it in different positions. for my situation, wide open is not the best. the flames blow way up the pipe.wide open is great to get started but i back it off alittle once its ripping. if i keep messing with it i will get as im sure you will. i hope to stop in soon.