evaporator set up

[maple flats]

I am planning to remove my temp wooden floor and put concrete in this summer. I was thinking about having air for combustion come up thru the floor. As I read the evap manual they suggest a pit for under the firebox. On my old evap I raised the unit on a platform of concrete blocks with a heavy tin hearth on top and had the evap set on that with a flat floor under the firebox. Who has a pit for ashes likely with a ash cover/door so air enters the evap thru either the air draft or thru a blower? What do you see as the advantage? All of the rigs I have seen set up have been put on a flat concrete floor. My newest idea if I have the pit is to make a concrete channel (or gutter) from there to the outside sloped towards the outside and make a set in cover to walk on. If I do this I would likely make it the entire length of the sugarhouse with a partition where the rear of the ash pit portion would be and each end slope down from this partition for drainage. Does anyone see a problem with this? I'm thinking maybe a 6" or 7" deep trench and almost as wide as the inside of the evap base. Then I could channel fresh combustion air to the draft blower and the ash clean out would be easy, could also run some conduit for power in this trench to run blower. What am I missing or not seeing?
Next question. I will be rebricking the evap as I took it out to move, as I do it, should i put some insulation board behind the brick? My unit now has none and my wife is still cold while running the rig, if i insulate the arch will the evap rate be greatly improved or if minimal I would tend to let some extra heat go to the sugarhouse but if rate is a lot better I would tend to tighten up the sugarhouse. For one thing I now have board siding without the batten yet, putting up batten would cut drafts greatly. Insulating is likely not in the near future plans but might be some day. Everyone's thoughts will be appreciated, thank you. (by the way, i HATE DOING CONCRETE, might even hire it done)
Dave

[Sugarmaker]

MF
I raised my Evaporator to get the height more to my liking. (8 inch) So I have a 8 in ash pit. I also have a blower and the sugar house seems plenty warm. Our walls are board and batten (Rough Hemlock) the battens really do make a difference.

If you have the brick out seems like a good time to add the extra insulation board. So you will get increased boiling rate and less heat loss into the sugar house, Better buy the wife a new coat or get those battens on.
I love the cement floor and was glad I hired the work done. Very pleased with the results. I have it sloped so that I can hose off the floor.
I do have a watter drain leading out of the floor under the back of the rig. I probably get some fresh air from here but most is just sucked through the leaks in the walls.
I buried my electric line under the concrete and came up under the rig near the blower with power for the blower and also added a receptacle to avoid tripping over cords. We have a 550 CFM blower and really don't notice it sucking the heat out of the room.

Usually about 30 -40 minutes on boiling and I have my coat off. I just have fire brick no insulation board. Also we do not have a insulated front on the old arch so it get rather warm in that area.

Regards,
Chris

[maple flats]

Chris, do you get a lot of sparks and fly ash from having the blower without an air tight front? With my 2x6 I am taking out I turned on the blower and there was a lot of ash that blew out, it seemed to then circle up and come back down into the syrup pan. For this reason I stopped using it. What is your experience?
Dave

[ibby458]

Before I insulated my arch front, and sealed it up, I got a lot of fly ash. I blocked part of the air intake of the blower, and that helped a lot.

THe ash in the pan didn't seem to hurt anything, just plugged up the filters faster. Also acted like filter aide. Cleanest syrup I ever made, after changing a LOT of pre-filters

[Father & Son]

Dave,
This year I put a 265 cfm blower on my 2 x 6 and it does not have an airtight front. When I first wired it up it was way too much and there were alot of sparks and fly ash. I solved the problem by wiring in a dimmer switch. Now I'm able to adjust output and it works fine.
Jim

[maple flats]

on my 2x6 this past season I had a larger blower but for the air inlet I built a slide gate to restrict the air moved. As soon as I opened the gate even 1/4" it blew sparks out the front doors and the air was blowing in the rear of the firebox, directly opposite of the air in draft for natural aspiration. With a wooden floor I couldn't risk fire and shut the blower off. In 07 with my new 3x8 I want to use the same blower and need to figure out how to make it work properly. Of course there will be a major difference, the wood floor is being replaced with concrete, and the footers/blocks are already in from before I put the wood floor down and supported the evap as the floor joists rested directly on the support from the footings which are 4' down. Not sure of the CFM rating on the blower but it is one my daughter got for me from Bascome that they sell for everything up to 3x10 rigs (it was used but still worked fine as far as moving air) This blower must be in the neighborhood of 5-600 cfm based on what 265's moved back when I was a furnace dealer, they used a 265 on the draft fan for 165,000 btu units, this likely moves double that, maybe a little more. I figure I will need a reostat because a dimmer would not work for a motor this size which was in the 6-7 amp class, if memory serves me I think the 265 from Grainger was slightly over 2 amp. I guess my biggest question about this part is.... Do you need a fairly air tight front to get satisfactory performance when using the blower?

[Sugarmaker]

MF,
Yes I get a little ash. I always thought that helped the flavor??? :lol: Not sure I can control this to much with my set up unless I shut off the blower completely while firing? I have hoods on both pans covering 80% of my pans so the amount of ash in the syrup has never been noticed during filtering. I really don't see much ash or sparks coming out the cracks of the door. I have the blower at the back also. I have homemade angle Iron grates with holes to allow the air to come thru. I run the blower on high even when firing unless the stack is blazing then I run on low for a while,
I do know that I got 10 times more ash when burning chunk wood than when burning pallets. In fact when burning just pallets I get almost no ash; just 3-4 gallons of nails for each 10 gallons of syrup made.
Chris

[WESTVIRGINIAMAPLER]

Chris,

If you ever go to an airtight front, you won't be heating the sugarhouse anymore. :(

[Sugarmaker]

Brandon,
Then I would have to insulate the sugarhouse to stay warm! :D. This old rig will probably never have an air tight arch.
Chris

[super sappy]

Chris- With the prices of scrap metal being higher than ever you may have stumbled onto the newest value added product in the maple industry.(burned nails = big profit in PA) :D Before I bricked my arch I used high temp gasket cement on all of the seams in the fire box.Especially between the arch front and sides.My blower was a small cage blower that only stuck out the front about 7 or 8 inches.To this I added a lenght of stove pipe with little legs to keep it level and a pc. of arch board to cap the end. I then drilled a series of holes in the pipe to direct the air wwhere I wanted it. It took some trial and error but , after I had a good pattern of various size holes, I was real happy with the rapid boiling on the syrup pan and once the draft was established I had little or no smoke or ash. I also insulated the doors with arch board.I rarely had to turn the blower down to fire.-SS