G.H.Grimm 3x10 raise flue????

[cpmaple]

Hello all,
Wondering if anyone has any pics or input on bricking a 3x10 raise flue g.h.grimm? It has a 3x7 flue pan an 3x3 syrup pan. With two baffles in place that is was is confusing me how to do from ramp back? Just picked this up yesterday with the brick but the owner was working an I spoke with the father in law so he did know. Please any help I would be greatful for. I've had many evaporator but first with baffles in place. Thanks cpmaple

[blissville maples]

From the ramp back out of the firebox behind the baffles lay some bricks on the bottom where the stainless steel sheets are and up the sides no need to mortar these. From there fill it to the top of the rails with vermiculite or sand tapering it in the back so as not to plug the chimney.

[tcross]

i run a 2.5x8 raised flue. it's made by thor. it also has the baffles/ramps behind the fire box. i've only put insulation down. never bricked it, and never filled it with vermiculite or sand or anything. my rig boils hard all the way to the back. i get 65 gph out of the rig with no modifications made to it. no blower, hood, preheater etc... you may not need to do anything back there besides insulate it? just y experience i certainly could be wrong?

[maple flats]

I ran a 3x8 Grimm raised flue for about 15 years. Great evaporator. To brick the firebox area, 1st decide if you will be adding air under fair and air over fire (AUF,AOF) if so do it now. You can run the AUF in under from the rear. Run an air tube in 4" diameter, and drill holes 1/2" holes if low pressure air every 3" in 3 rows (if high pressure drill 5/16" holes) one top center and one facing each outer edge of the grates.
Then firebrick from the grates up until you get to 7" below the top of the arch if adding AOF. (if AOF, make a manifold to go all around the firebox except over the doors. Then in the manifold have a 5/16 nipple welded in to the manifold every 6", pointing downward at about 12 degrees. These nipples will be your AOF nozzles) If no AOF, continue with the bricking all the way up to fill just under the frame siderails. Across the back you can just lay loose firebricks along the slope until you are about 2-2.5" below the flue pan. Then add vermiculite to fill the space from there back to the rear most cross section. Level it at 2.5" below the pan. Run a firebrick rearward from the back cross section, and stand it upright to support the top of that section divider. Then fill the space above the vermiculite with full firebrick so it won't blow away, up the stack.
Then fill the remaining space behind the rear cross divider, by laying firebrick on the bottom and along each side.
To buy the vermiculite buy it from a real greenhouse supply, other sources would cost several times what a greenhouse supply charges. Buy it in 6 cubic foot (CF) or larger bags, you will need about 24 CF. Do not give in and use sand, it will be cheaper but way too heavy without adding more legs to support it.
When the flue pan is set on the arch, the brick over the vermiculite should be about 1/4-3/8" below the flues, forcing the heat thru the flues. Make sure your stack is at least 20' tall (2 times evaporator length)., Higher is fine, less not good.
Any questions just ask.

[cpmaple]

I ran a 3x8 Grimm raised flue for about 15 years. Great evaporator. To brick the firebox area, 1st decide if you will be adding air under fair and air over fire (AUF,AOF) if so do it now. You can run the AUF in under from the rear. Run an air tube in 4" diameter, and drill holes 1/2" holes if low pressure air every 3" in 3 rows (if high pressure drill 5/16" holes) one top center and one facing each outer edge of the grates.
Then firebrick from the grates up until you get to 7" below the top of the arch if adding AOF. (if AOF, make a manifold to go all around the firebox except over the doors. Then in the manifold have a 5/16 nipple welded in to the manifold every 6", pointing downward at about 12 degrees. These nipples will be your AOF nozzles) If no AOF, continue with the bricking all the way up to fill just under the frame siderails. Across the back you can just lay loose firebricks along the slope until you are about 2-2.5" below the flue pan. Then add vermiculite to fill the space from there back to the rear most cross section. Level it at 2.5" below the pan. Run a firebrick rearward from the back cross section, and stand it upright to support the top of that section divider. Then fill the space above the vermiculite with full firebrick so it won't blow away, up the stack.
Then fill the remaining space behind the rear cross divider, by laying firebrick on the bottom and along each side.
To buy the vermiculite buy it from a real greenhouse supply, other sources would cost several times what a greenhouse supply charges. Buy it in 6 cubic foot (CF) or larger bags, you will need about 24 CF. Do not give in and use sand, it will be cheaper but way too heavy without adding more legs to support it.
When the flue pan is set on the arch, the brick over the vermiculite should be about 1/4-3/8" below the flues, forcing the heat thru the flues. Make sure your stack is at least 20' tall (2 times evaporator length)., Higher is fine, less not good.
Any questions just ask.

Maple flats it has auf already grates already installed an blower, blower distribution box is as wide as the arch just blows into firebox. Came with 21ft of chimney 16" which seems large for this size rig but that is what the base section is so that is what it will be. The gentleman I got it from said he got 75-90gph off from it depending on how hard you fired it an wood dryness. No hood or pre-heater this year for there will be a hood for next. Price was very fair so I jumped on it might be a tad bigger then what I need but with my work I never know if I will be stuck over or not so I could go 2-3 days before I can boil. Hoping not but the chance is there. I didn't want to deal with a ro with draining it an heating from freezing at night. Thanks to everyone for the input cpmaple will keep you all posted on the outcome or if I have more questions.

[cpmaple]

One other question what do I do about the front of arch? Do I try to get fire brick to motor to the cast or fire blacket insulation then how do I get that to stay? Or do I leave that alone the cast front an don't worry about the little heat loss so my father in law can stand there an stay warm?

[blissville maples]

Usual brick the front on either side the door. The door itself if it's newer should have insulating Arch blanket fastened to it. If it doesn't I would try to incorporate that you want to keep the heat underneath the syrup not escaping through the steel.

You're probably going to wish you had an ro!! It's really not hard keeping them warm draining and all of that well worth the time and investment. You can pick up the older d&g leader style arrows for 6-8,000. I bought a two post for 75 added another post for 3, 000 a recirc pump for another 1500 and now I have a machine that will produce 15-20% at a rate of 1.5 gpm.

I have a 3x10 inferno with a steam away and we typically boil off about 160 to 180 gallons of sap an hour making anywhere from 30 to 40 gallons an hour around 16 to 18% concentrate.

[blissville maples]

There's usually clips and washers on the door to hold the insulation blanket

[tcross]

if you have regular cast iron doors, it's going to be hard to keep insulation on them. my arch is insulated and bricked, but the door is not. heat does escape and i'm sure you loose a little bit of boil rate. not sure if you can weld to cast or not? if you can, you could weld a few bolts on and put the insulation over the bolts and put some washers/nuts on. over time you'll have to replace it.

[maple flats]

My door was not insulated. On my 3x8 version of what you have (3x3 syrup pan, 3x5 flue pan, I got generally 60-65 gph but if I pushed it real hard, I could get 75 gph, I'd think with your 7' flue pan you should be able to get 100-110 gph, if feeding it dry wrist size wood on an 7-8 minute refuel schedule with your AUF giving the needed draft. If split larger or not dry, maybe 75-80 gph.
My arch had a hood and preheater under the hood which fed the float box with 170-180F concentrate until a draw off at which time the temperature dropped to 110-125F.

[blissville maples]

Stack temperature!! Can't stress this enough don't worry about feeling the evaporator every so many minutes if you really want to boil at your max rates you need to keep your eye on the stack temperature never let it go under 700 trying to keep it between 800-900 will keep you making syrup

I COULDN'T dream of evaporating without a stack thermometer it's a necessity