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Amber Gold
07-07-2008, 10:41 AM
I'm converting my 14x20 garage into a sugarhouse for my 2.5x6.5 evaporator. The roofs rotted so I'm tearing it all off and rebuilding it. Based on what I've read, I've determined that the cupola needs to be the same size as the evaporator, so I'm going to make it 3x8 for when I get a new flue pan down the road and stretch it. I'd like to place the evaporator 3 feet off the left hand wall so I can put my canning/filtering/shelving on the right hand wall and creating more for visitor/customers versus if the evaporator was centered. This would make the evaporator 2 feet off-center from the cupola. Will it still work properly being off-center? Would it make a difference, or help, if I went with a wider cupola so more of the evaporator would be under it? I do plan in the future to get a new flue plan with a hood and preheater, but that will likely not be for a couple of years.

Thanks

Russell Lampron
07-07-2008, 11:11 AM
Yes it will still work. Royalmaple has his set up that way and doesn't have a problem with steam not venting out.

tuckermtn
07-07-2008, 06:32 PM
we have the same off-set to the left side...and a little toward the back...and we still vent pretty well...we started with a 2x6 and sized the cupola accordingly...but now we have a 2.5 x 8 and the evaporation rate is twice what the 2x6 was, so we have been having a hard time with condensation (metal roof)...put some ridgid foam between the rafters which has helped.

so go bigger if you can with the cupola sizing...You won't regret it...

Haynes Forest Products
07-07-2008, 07:54 PM
You can make a steam hood cheaper and faster than you can make a coupla
wish I did it the day the 3X10 went in. I spent the July 4th week boiling water to set up my oil burner and clean the pans from this spring. I tried to boil without the hood and the heat was unbelivable in the cook shack that you had to run into a sana to cool off. I put the hood on and it was bearable in 90 degree temps.

Amber Gold
07-08-2008, 07:47 AM
Maybe I'll make it 3x10. I'd rather have too much than not enough.

How can building hoods for the flue and syrup pans and buying all the stack, roof jack, and stack cover be cheaper than building a cupola? That stuff can get pretty expensive. Besides, I'm planning on stretching the evaporator in the future and wouldn't want to put all that money into the stacks and hood and have to replace it. Then again the stack size will likely be about the same size for the larger flue pan. Also if I set up my stack roof penetrations for a 2.5x6.5 evaporator and then stretch it the spacings will be different.

Thanks for the advice.

Sugarmaker
07-08-2008, 06:06 PM
Josh,
Sounds like you will be expanding so maybe the cupola will work for you for several years. The hoods and steam pipes are well worth the money and or effort once you settle on a evaporator and location.

Chris

sapman
07-08-2008, 10:42 PM
Josh,

I think I have to agree with you about the money. I haven't really priced what a cupola will cost me to build, but when I priced a stainless hood and stack for my 2.5x3 front pan, it was going to be just about $1000, and that was two years ago! I can't believe a cupola would be that much.

Tim

Amber Gold
03-01-2009, 03:12 PM
I fired up my evap. yesterday and when things are really ripping it's getting pretty steamy in the sugar house...not unbearable, but I expect everything to go up. Evap. is 2.5x8 and the cupola is 3x10 with 18" tall doors...thought that would've generated enough draft. Also it didn't matter if the doors were open or closed same draft situation.

Any ideas to help get everything up?

I also put sheathing on the roof I'm still getting condensation dripping down. Due to the steam problem I'm not sure what it's dripping from.

3% Solution
03-01-2009, 07:00 PM
Hi Josh,
What I have always been told is the square feet for the vent needs to match or be larger than the size of your pan.
So if we do the math, you have a 20 square foot pan and you have 30 square feet of vent.
I would think you should be good.
Have you let the heat build up in there to get the convective current flowing?

Dave

Amber Gold
03-01-2009, 08:14 PM
Dave,

It was about 28-30 out last night when I was boiling and never really warmed up in the sugar house. I think it was about 34 inside.

Haynes Forest Products
03-01-2009, 08:18 PM
You need to think about what is happening Hot air rises hot air with water vapor will rise BUT not like hot dry air. Steam is hot water vapor in warm air and its HEAVEY. Steam will not leave a closed area unless there is makeup air. What is make up air its the air that replaces that air that is leaving the area. Hot air will not just flow out of a room/area without air coming into to replace the hot air/steam that is leaving. If you open a window or door to replace the air/steam that you want to evacuate the room it cools the steam back into rain and bingo thing dont move..............If you look at your house the reason you have COLD air returns is to allow cool air to leave/get sucked out of a room so new/hot air can come into the room.

COOL HEAVEY STEAM LADEN AIR WILL NOT RISE IT WILL SINK

3% Solution
03-01-2009, 08:58 PM
Amber Gold,
Your a firefighter, right?
Think about the law of heat, hot is attracted to cold.
Warm air rises, cold air sinks.
What happens when the boys inside get to the seat of the fire and put water on it .............. steam.
Ask anyone of them what it's like in there when that water turns to steam, it isn't a fun place to be.
Now as the guys on the roof get the hole opened up what did you see from the outside ................ smoke and steam coming out of the vent hole.
That's how you can tell if the guys on the inside have hit the fire ........ the smoke turns to white, which consists of steam.
So, if you get the inside warmed up the steam will go out the top, it's the convective column, it's "The law of heat."
Hope this helps.

Dave

Amber Gold
03-01-2009, 09:12 PM
Thanks Dave. Some cool info in there. 95% of our calls are MVA's. I've been on the dept. for 2 years now and have only been to 2-3 legitimate house fires, a couple of chimney fires, and other misc. We don't get many structure fires. So if I boil on a warmer day I should have better luck? Thanks

Haynes Forest Products
03-01-2009, 09:23 PM
And lets not forget what happens if you dont have make up air and your pouring water on the fire and there is roof venting going on and then all hell breaks loose and windows blow and air rushes into the fire area.

Hop Kiln Road
03-02-2009, 06:09 AM
Hi Josh - Sounds like you're really making progress. Takes a lot of time and energy to get an integregrated system functioning. Depending on the temperature, air pressure and wind, I open either one side or both doors. If it is either lower pressure or high temperature outside sometimes it takes a while to establish a heat column. A hood makes a big difference. Setup a line and barrel for Norman the other day and he's going to take a try at running my evaporator. Good Luck. Bruce

Amber Gold
03-02-2009, 12:05 PM
Bruce, getting there, busy and having fun. Glad to have a little run to shake things out and work on some bugs before it really starts coming. Glad I upgraded to the larger/newer evaporator...wish I had more time to test fire, find/fix leaks, and etc. Things were coming down to the wire getting things completed (tubing, vacuum, evaporator) in time, but things are coming together. Tell Norman I said hi and how things are working out. Good luck and hopfully you have another banner year...still can't believe you got 0.4 gal/tap off gravity tubing. Amazing! I'm hoping/praying to the sap gods I'll get that on vacuum.

Hopefully steam issue resolves with warmer temps.