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SmellsLikeSyrupNH
11-12-2018, 08:28 AM
Good morning!!

Yesterday I tried my 1st test boil with my new Smoky Lake 2x6 raised flue pans. I put about 1.5" of water above my flues and in my syrup pan. Got a really nice boil going in my back flue pan and it happened pretty quickly, not as fast as I was expecting, but once it was going it was great. My front pan, NEVER got to a boil. :cry: Everything except the arch is new to me. New Pans, Stove pipe, Auto Draw system.

I'll describe my whole setup:

- 2x6 Smoky Lake Raised flue pans.
- Dayton Model 1TDT2 549cfm squirrel cage blower.
- 3ft base stack and 12ft of 8" stainless stove pipe.
- Arch is about 95% air tight, its not perfect but pretty good.

What I noticed was as soon as I turned off my blower and opened the door I could see my fire being pulled back by the natural draft of the stack. When I would close the door the blower would start spinning on its own just from the natural draft sucking air into the arch. My from pan never got higher than 211.6. Just couldn't get it to boil. After an hour of trying I just gave up. (Patriots game was also about to start ;-) )

My questions are, could my stack be sufficient enough that I dont even need the blower? How can I get the heat to stay in my front fire box longer?

My next steps that I have come up with.
- Going to remove the pans and reconfigure the arch. I believe I have too much space between the fire blanket and rear pan. Thinking if I shrink up the space it will keep the heat in the front longer.

I have playground sand as the base with fire blanket laid over it.

- Try another boil without using the fan at all.

Any other ideas?

Pictures attached to give a visual

Thanks!
-Scott
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raptorfan85
11-12-2018, 03:12 PM
I'm not sure if that's just the fire getting going or not but it's pretty small. You want the firebox full front to back and side to side and about 2/3 high. I don't have raised flues but it's my understanding that you want the fire blnaket as close to the bottom of the flues as possible. That will force the heat on to the pans better. The blower is really big for a 2x6. It should only need to be about half that size. I would try blocking off the intake about 1/2 to 2/3 with some duct tape and see what that does. You are probably blowing some heat up the stack.

Good luck!

maple flats
11-12-2018, 03:17 PM
In picture 2, is that all the fire you are using? You want to fill the firebox 2/3 full and burn it as hot as you can. As long as you have sap, near syrup or even water in the pan is no such thing as burning too hot, you want it the hottest you can get.
How much space do you have under the flues? It should be 1/4-3/8" max, that forces the heat up into the flues and at the same time gives you more heat in the front pan. That (less space under the flues) and a blazing fire under the pan will give you the boil you expected, and likely even more.

maple flats
11-12-2018, 03:25 PM
I also agree on the blower, too much air, damper it down. Also, just run the syrup pan at 1", but it should also boil at 1.5, just not as hard.

SmellsLikeSyrupNH
11-12-2018, 03:29 PM
Guys thats just a picture of me getting the fire going....Just wanted to show a picture of the fire box. I stuffed the box full once the fire was going. Will definitely redo the back of the arch to make the the space smaller under the flues. Also I do have a damper on the blower to throttle back the air flow. I agree its a BIG blower, but it has worked well for me in the past before I did all these upgrades.

maple flats
11-12-2018, 05:06 PM
OK on the fire then, it just didn't look right. When I start mine I lay the whole fire up, to 2/3 full, then use weed burner torch to light it. Going fully burning within 2-3 minutes and ready to add a full arm load after 9 minutes. The picture just confused us, or at least me.

raptorfan85
11-12-2018, 05:34 PM
The picture of the fire had me off a little too. I would try closing up the space under the flues first. That will push the heat up onto the pans and keep it under the front pan a little longer. Also try with just natural draft and then with the blower dialed way down. See what that does first.

Russell Lampron
11-12-2018, 07:25 PM
Water boils differently than sap. What doesn't look like a good boil with water will look right with sap. The gap under the flue pan needs to be filled to the rails, that directs the flames into the flues and helps keep more heat under the front pan. I didn't see your blower. I had a huge one under my old arch and damped it down to get the air flow where I wanted it. It's normal for the draft to pull the flames back into the arch. If the pictures with the stack in them were taken after your test boil you didn't get it too hot. Mine's got a nice purplish patina.

Do you have any firebrick in the arch? Ceramic blanket doesn't hold up to well with wood being thrown into it.

If you can come up to Loudon I can show you my arch and how it's bricked.

wnybassman
11-12-2018, 07:38 PM
When I first did a test boil on my current rig I barely got a boil going in the back compartment of the front pan. The front two compartments I never got a boil going at all. For whatever reason water and raw sap (at the beginning of the season) takes forever to boil in the front pan. Once the rig is sweetened it seems to take far less time.

As far as getting things to a boil faster, I criss-cross my fine kindling horizontally all the way up to the bottom of the syrup pan. I start the criss-cross on a couple 2x4's on edge so I can stuff paper under the kindling. I've gone from a cold start to a boil in the rear pan in less than five minutes from lighting the paper before. Most times it is closer to 8-10 minutes though.

SmellsLikeSyrupNH
11-13-2018, 08:07 AM
Thanks everyone, i will do the adjustments and hope for the best, not working on it today, will have to wait until Friday or the weekend.