Controling Heat Output; 16" Firepot Baseheater

Not with my Wings Best (a G6 copy), during warm periods I just push in SS bolts and seal off that leak too. I have run my WB at 150* for days. Notice my door seals as well. I have an Our Glenwood No. 9 (same as the Crawford) and at ultra low heat outputs it has a slight edge but at higher heats the G6 will definitely run better. Everyone of the above are fantastic stoves and you need to play a little to get the most out of them.

and the hole where your finial attaches is far from air tight.

and that does not matter.

coalnewbie wrote: I have an Our Glenwood No. 9 (same as the Crawford)

Almost true...but not quite

Whereas the Gwood only has gasses travel down the sides of the base, the Crawford 20, 30, 40 & 50 gasses also pass below the ash pan adding significant radiant surface area.

cpi wrote:

Sunny Boy wrote:..., a pipe elbow with a check damper built into it.
Paul

Paul,

Intellectually, the elbow with a check damper makes sense to me, providing I believe that the chimney will not become obstructed by a random freak event during my absence.

But, my gut says be afraid.

If I were to see over a long period of time that my chimney always maintained a solid draft on warm days, without heat added to the flue, then I'd fear less. How about you? Without experience, I am just extrapolating from theory.

The built in check dampers in the suspended pot stoves are indeed an attractive feature. Lets see what evaluation [a post soon..] of my chimney turns up. So far, I have tried not too get excited about any particular stove or type. Regulatory compliance, insurance, coal storage and availability, have all conspired to turn this project into a hard push uphill.
Chris

Understandable Chris - I was too. But that worry went away once I had the mano installed and could accurately see what the draft was - instead of worried guesses.

And, you only need the check damper if you have a decent, or too strong, draft. If your draft is weak that will limit how well the stove will put out heat, so using the check damper, or not, won't be what you have to worry about.

I spent some daytime hours watching the mano while I experimented with various check damper openings in combination with adjusting the other stove/pipe dampers - during still and windy conditions- until I felt confident to use it overnight. With practice you'll learn how much check damper opening yields what temp output and how steady and how long it will maintain that.

And, it doesn't take much check damper opening to slow the fire down nicely. Because it's also meant to use wood the check damper on my range has a greater total square opening than the elbow check damper of my G6. But, with the range check damper on the coldest of nights I never need more than 25% opening. At that, it's less square opening than the total of the gap around the fully closed butterfly plate of the 6 inch Field Control baro I have on my oil burner.

A mano will show you more about how well your operating your stove and allow you to run it over a greater range of temps and do so more efficiently. And because of that I was better able to adjust the dampers and not waste heat up the stack. What I saved in coal paid for the mano in just a few months.

Paul

Whereas the Gwood only has gasses travel down the sides of the base, the Crawford 20, 30, 40 & 50 gasses also pass below the ash pan adding significant radiant surface area.

Incorrect.

Please post a pic , I'll learn something. I know the 109 & 111 only go down the sides.

coalnewbie wrote:... I have an Our Glenwood No. 9 (same as the Crawford) ...

Yes you do. I believe that your No. 9 is that fine looking version that belonged to William. I have a thing for that stove. From the images that I have seen, the 109's that followed do not posses the same aesthetic qualities.

Is it that the door on your wings does not seal well enough for your needs even when it is mechanically 'original,' or is the seal a band aid? Has the closing of the built in over fire passages during warm OAT's resulted in a measurable result? i.e., lower CO readings outside the stove or improved ability to keep a low burn alive?
Chris

Sunny Boy wrote: ... And, you only need the check damper if you have a decent, or too strong, draft. If your draft is weak that will limit how well the stove will put out heat, so using the check damper, or not, won't be what you have to worry about. ... Paul

Paul, thanks for that; you prompted me to think, instead of idly stringing together unrelated pieces of information.

OK, so the concerns which prompted me to open this topic were based on not thinking through how the combustion process would work. Perhaps the Subject should be restated. Anybody have suggestions?

Writing these thoughts out helps consolidate my understanding. Please anybody, pile on where you see incomplete understanding.

If attempting to run a stove at a low burn rate with a weak draft, either; i) the fire dies, ii) more over fire air is required and thus more heat for the flue or, iii) submit and run direct draft.

Attempting to run a stove at a high burn rate with a weak draft is a lost cause because it will be impossible to draw enough combustion air through the fuel.

Back to were I started; trying to deny the reality that if my chimney is deficient, I am going to have to correct it or pass. Chimney details soon...
Chris

fifthg wrote:"readily"controlled? There is no question it could do an excellent job,but if you have never operated one,there would be a learning curve. So,"it depends".Maybe not so readily for you,with all due respect,as your questions lead me to believe you have not.Do it.You will be glad you did.Welcome to the forum.

SCORE! Second post in the thread, right on the money. However, no extra points for the thought provoking dialog.

Chris,

There are too many unique variables to say with certainty how well any stove will work for you, much less how low you'll be able to actually run it and how hot, or not your place will get. At best we can only give you guesstimates based on our experiences with various stoves in other setups. But, you can up your odds a lot if you follow common rules of chimney and stove installation/setup, with a well known stove design, and one in very good condition. That'll get you very close to what the average advice works out to.

However, there is one certainty that helps you figure out and deal with some of those variables. That is, no matter what stove you get a mano can tell you to very close tolerances ( less than .01 of an inch of water column) how good the draft from your chimney set up is, how tight/controllable your stove is, and most importantly, what your draft is doing and what affect on draft your damper settings are having.

Paul

we can also cut to the chase to a certain degree by knowing the following :

1) is your chimney more or less centered in the space to be heated ? if up an exterior wall, inside or out ?

2) is it steel or masonry ? if steel and exterior does it run up the inside of a chase protected from direct weather impact ?

3) is it atleast 3 ft. above the highest point of the roof ? are there trees of similar height with in 30 ft. of the chimney cap ?

4) using 36" above the floor as the top of a stove collar what would the total rise be from there to the chimney cap ?

this info can give a fairly good expectation of chimney performance.

steve

Can we assume this house has windows that open. Bingo !

KingCoal wrote:we can also cut to the chase to a certain degree by knowing the following :
1) is your chimney more or less centered in the space to be heated ? if up an exterior wall, inside or out ?
2) is it steel or masonry ? if steel and exterior does it run up the inside of a chase protected from direct weather impact ?
3) is it atleast 3 ft. above the highest point of the roof ? are there trees of similar height with in 30 ft. of the chimney cap ?
4) using 36" above the floor as the top of a stove collar what would the total rise be from there to the chimney cap ?
this info can give a fairly good expectation of chimney performance.
steve

Steve,

The 80 year old fieldstone fireplace chimney under consideration is original to the house; located midpoint on the east-facing long-wall. It has two flues and overall dimensions of 72” wide x 34” deep; half of the profile is inside the house. Its internal construction is an unknown to me.

The smaller flue is constructed of 8” square tiles = 6.5” ID, with a 6” flexible liner installed. It runs down to the crawl-space and serves a Nat Gas boiler installed in a partial basement.
The large flue which serves the grade level fireplace has 16” square tile = 13.5” ID, which is clearly too large a volume for any stove appropriately sized to my heating needs.

With the chimney at ambient temperature on a 65° day, a purposely smoldering fire exhausts without any back-drafting. This may be as much due to good fireplace design than draft. The fireplace chimney does noticeably draft most of the summer if allowed.

Chimney height from [hearth] floor to top of flue = 17’ 4” – effective height of 14’ 4”

Peak of house 19’ 4” – [see photo at beginning of topic] which is 2’ higher than the flue outlet. The flue outlet is 12 feet from the [9/12] roof on a horizontal plane.

The only objects other than my roof within 40’ + of the flue termination are hardwood trees, all of which are in excess of 65 - 70’ tall; their branches begin well above the flue outlet.

Site elevation is about 500’ on the west slope of a wooded mountain; 75 feet directly behind and above the site is a three story home. The town is surrounded by a ring of small mountains. Snow does not drift much here.

The crawl space & basement have light to moderate air infiltration and are warm in the winter from the heat of a 100k BTU Nat Gas boiler supplying heat to bedrooms, partial basement and serving an indirect fired hot water tank.

The living space has very little air infiltration, mostly at the 2 entry doors. The area 8’ above the floor is very tight and has no ridge, gable or soffit vents.
Chris

Looks to me like if you reduce the size of the flue, by either a terra cotta, poured masonry, or AL294C SS, you should not have any problems generating sufficient draft to run an antique. Also, you can inexpensively add some height with a top extension.

Joeq's 111 ran last fine year, in base mode, in his garage with about 5 feet of TOTAL chimney

cpi wrote:
With the chimney at ambient temperature on a 65° day, a purposely smoldering fire exhausts without any back-drafting. This may be as much due to good fireplace design than draft. The fireplace chimney does noticeably draft most of the summer if allowed.

This was the most important things I got from your post. If you are planning to use this flue for the stove you want to add..............I suggest no changes at this time.

SWPaDon wrote:

cpi wrote:
With the chimney at ambient temperature on a 65° day, a purposely smoldering fire exhausts without any back-drafting. This may be as much due to good fireplace design than draft. The fireplace chimney does noticeably draft most of the summer if allowed.

This was the most important thing I got from your post. If you are planning to use this flue for the stove you want to add..............I suggest no changes at this time.

+1.

With a chimney that drifts that well, just block off the chimney flue around the stove pipe by packing fiberglass insulation around the pipe and you should be fine.

I'd still recommend one of these, no matter what coal stove you do get. http://www.amazon.com/dp/B009PAN3C8/ref=biss_dp_t_asn

Paul