Baro question

I know folks are always arguing the merits of barometric dampers. Don't want to get into that . . . .

But I'm finding that due to the success of my secondary combustion system on my handfed bit. stove, my temps and draft are quite high during and after the volatile stage of my bit coal. If you've followed the recent posts in the bituminous forum, you can see that I can get major heat from the volatile stage. It would be nice to temper this stage some. Several hours after a fresh load, the stove can get to 650F, and thus I'm having trouble getting 12 hours from a load of coal. Prior to the secondary air system, I didn't have trouble getting 12 hour burn times.

Seems like a barometric damper would help control this, but I'm afraid to install one on a bit. handfed stove. Would a baro possibly allow enough oxygen into the chimney that I would begin to burn any leftover gases within the chimney, creating a dangerous condition? Or would it be a problem if/when I occasionally get backpuffs/explosions in the stove?

Any thoughts on adding a baro to a handfed bituminous stove?

Steinke

i seen a thread on here not to long ago where berlin said to never put a baro on a bit stove. i just did a quick search, but came up short. i ll keep lookin

Berlin mentions that is this thread - http://nepacrossroads.com/about5971-15.html?hilit=baro%20bituminous#p63095

I run a baro with bituminous coal and have no trouble controlling the draft

and getting long burn times only limited by the amount of coal in the boiler

and if it falls down or not.The coal I burn creates a lot of coke and if it

melts together too much it will not fall and creates a hollow spot without

much fuel to burn. It never goes out but gets low on heat.

My baro is set to .06 and is about 6'-7' from the chimney so if it ever gets

a puff back the long pipe absorbs the gases so I don't get a lot of dirt and

gases in the basement.

I feel its essential to get a steady draft and would recommend one and if

possible put it as far as possible from the stove.


BigBarney

I always used a baro on a bituminous fired appliance. Here was my response in the previous thread.

Chappee hand fired boiler

Terry

Since this is in the unattached garage, I'm not too worried about an occasional backpuff. Just don't want to burn the garage down. Sounds like a few people (OK, BigBarney at least) using a baro on a bituminous handfed. I may try it and see.

If I do, I'll post back with results, so others can learn from my mistakes/successes.

Thanks.

Steinke

I went and read the other thread about baros on bit. stoves. Sounds like most baro discussions - people all have opinions, and they rarely agree. I think I'll try it though and see. If I don't save coal, it's not worth it. But I frequently see above -0.10" WC draft during the first few hours after loading. Seems like too much to me.

When I bank the coal prior to loading, it definitely releases the volatiles slower. Just hoping that a baro will help even more.

steinkebunch wrote:(OK, BigBarney at least) using a baro on a bituminous handfed. I may try it and see.

This is my first year using a stoker (Will-Burt). Don't know how I got along without one. I was talking about hand fed boilers with boros which I have used for ~ 30 years or more with no problems. Interesting project you have there.

Terry

In any stoker, i highly reccomend a baro, and in many cases it won't burn well at all without one. In a hand-fired appliance, with certain bituminous coals, and proper firing practices you can reduce the risk of any backpuff. Unfortunately, reduced risk doesn't mean no risk and if the appliance is located in the living space it is my opinion that it is not worth the risk to cover you home with soot to save a few $ on (an already inexpensive) fuel. As far as having trouble controlling volitile release w/out using a baro - i would say that you have an appliance that's not as air tight as it should be or the ratio of secondary air to underfire air needs adjustment; i've never had an issue getting a long burn with proper under AND overfire draft control. You don't need much secondary air to combust the volitiles- and Steinke, bear this in mind, the more heat you generate above the fuelbed to more thoroughly combust the volitiles, the faster the (now hotter) coal will release the volitiles; too much secondary air will also give you high flue temps such as you're experiencing. Trying to eliminate some smoke and increase the efficiency of the stove is a good thing, trying to eliminate all smoke in a hand-fired stove will lead to other problems. I've played around with barometric dampers on hand-fired bituminous stoves, while they do offer increased controllability, as i mentioned, i don't believe that the improvement is such that it warrants the risk of sooting up your home or basement. In a garage, where there's less concern about cleanliness, the risk may be acceptable.

I use a baro damper on my handfed stove as well and never had any puffbacks, soot buildup on the baro flapper or any other issues. My old stoves are much easier to control with a baro however, just because it works well for my situation does not mean everyone burning soft coal should go out and get a baro damper.
I know opinions vary greatly on baro dampers so all I can say is based on my own experience, baro dampers work very well on my stoves... I'm not basing this on assumptions, guesses, opinions based on what others have posted about it etc....it's my own hands on experience.
I agree with bigbarney that it's best if the baro is mounted further up the stove pipe than you commonly see on stokers/oil furnaces.
I also agree with Berlin that stokers should use baro dampers.

Berlin wrote:As far as having trouble controlling volitile release w/out using a baro - i would say that you have an appliance that's not as air tight as it should be or the ratio of secondary air to underfire air needs adjustment; i've never had an issue getting a long burn with proper under AND overfire draft control.

I know it's not airtight. My boiler was cast in the 50's with no gaskets anywhere. It weighs over a thousand pounds assembled. I could have the doors machined to accept gaskets, but the baro worked fine for all the years I hand fired. I've had to adjust the over/under air settings for different coals that I've burned over the years, but that was easy enough. Long 'controllable' fires with no excessive coal usage. Not much room for improvement there, until I got the Wil-Burt.

Terry