Baro Damper Setting

Dallas wrote:

coaledsweat wrote:With most hand fireds a baro is a required device.

Please explain, "why it's required" on a hand fed stove. Please explain, why those in coal country, who grew up with hand fired units, were able to exist without baro dampers? What will happen, if a manual damper is used instead of a baro damper?

Not much, if you are accustomed to using the manual damper. But if you have ever run one on a wood stove, (used only because it's _much_ more obvious when a woodstove isn't playing nice), you know that weather and humidity changes can cause a stove that has been burning gorgeously for a week to suddenly start dumping large amounts of smoke into the room.

Baros are set-and-forget, and take that learning-curve out.

The difference is, when your woodstove malfunctions, your house fills with smoke and you notice. When your coal stove malfunctions, you die in your sleep.
(Cause everyone tests their multiple CO detectors weekly, like they are supposed to, right?)

I never had a baro damper on my wood stoves. A manual damper pretty much buffers the fire from instantaneous chimney draft effects. Not many of the old timers died from CO poisoning, because they had no baro damper.

Dallas wrote:I never had a baro damper on my wood stoves. A manual damper pretty much buffers the fire from instantaneous chimney draft effects. Not many of the old timers died from CO poisoning, because they had no baro damper.

Oh.. more than you might think died from that.

But, the point is, we don't all live in drafty old houses like the "old timers" did, and we didn't all grow up with dampers and learn innately how to use it. While those of us who grew up in farmhouses know it instinctively, Joe Yuppie in his McMansion who has never used a combustion device in his life might have some issues with it. I think they are code in some places, because while they don't hurt, they can certainly help.

Personally, I can't see where a baro damper helps, in regard to CO poisoning. The factor creating a CO problem would be "poor draft". If anything, a baro damper will reduce draft ... there is no way they can increase it. I would sooner think, their place is reducing "over firing" and limiting the chances of a house fire.

Dallas wrote:Personally, I can't see where a baro damper helps, in regard to CO poisoning. The factor creating a CO problem would be "poor draft". If anything, a baro damper will reduce draft ... there is no way they can increase it. I would sooner think, their place is reducing "over firing" and limiting the chances of a house fire.

Right. But you either want a baro or manual in most installations. One is basically fool-proof, and one is a fool magnet.

Dallas wrote:

coaledsweat wrote:With most hand fireds a baro is a required device.

Please explain, "why it's required" on a hand fed stove. Please explain, why those in coal country, who grew up with hand fired units, were able to exist without baro dampers? What will happen, if a manual damper is used instead of a baro damper?

OK, required they aren't. Maybe "required" is too strong a word. The baro allows the chimney to draft at its pleasure, whatever the chimney wants the baro allows it to have. But at the same time it limits the draft to the unit to a set point. Typically, beyond the recommended set point, you are wasting heat. It should prevent over firing the unit too which can be dangerous. So it isn't required if you don't mind wasting money. Everyone in coal country should be able to exist without one, for some it will just cost them more money.

The hand damper is a restriction in the pipe. That limits the draw but cannot limit maximum draft. It also can cause a positive over fire draft.

I use both as they have two different functions.

Dallas wrote:Personally, I can't see where a baro damper helps, in regard to CO poisoning. The factor creating a CO problem would be "poor draft". If anything, a baro damper will reduce draft ... there is no way they can increase it. I would sooner think, their place is reducing "over firing" and limiting the chances of a house fire.

A baro damper only reduces draft down to it's set point.. what it reduces is OVERDRAFT.

If you used a manual damper INSTEAD of a baro damper, then if the weather changed in the middle of the night from cold and windy to warm and no wind a baro damper would just not open, the maximum draft and flow would be available to draw CO out of the stove.. But if equiped with a manual damper, the manual damper would be still set where it was for the cold/windy weather... with the resulting restricted flow and cooler chimney, resulting in less draft... and possible CO in the house.

That's how a baro damper helps in regards to CO poisoning.

CBT69: Right. But you either want a baro or manual in most installations. One is basically fool-proof, and one is a fool magnet.

I like that!!

Greg L

LsFarm wrote: the maximum draft and flow would be available to draw CO out of the stove.. But if equiped with a manual damper, the manual damper would be still set where it was for the cold/windy weather... with the resulting restricted flow and cooler chimney, resulting in less draft... and possible CO in the house.

I of course, disagree to some extent.

I don't believe a manual damper gets "set for cold/windy weather", I know mine doesn't, but I do believe it buffers the fire from those changes. I believe the MPD actually keeps the chimney temperatures higher than a baro damper. Why? Because, with a MPD, the "temperatures of the fire" are rising up the chimney, rather than a chimney draft temperature, diluted with room temperature air.

Taking a look at another aspect ... especially on newer homes, but not exclusive to newer homes, in order to to have sufficient draft for complete/safe combustion, there has to be adequate air infiltration. This delicate balance can be upset, by the operation of a clothes dryer, furnace, bathroom fan, range exhaust, etc. Now let's say we are running right on the ragged edge of adequate combustion air, the baro damper opens and additionally drafts combustion air out of the house. Now, we've created a negative pressure within the house, through the baro damper. .. fire dies down, draft dies down, CO enters negative pressure space. These various scenarios are concerns of safety professionals.

Dallas wrote: Taking a look at another aspect ... especially on newer homes, but not exclusive to newer homes, in order to to have sufficient draft for complete/safe combustion, there has to be adequate air infiltration. This delicate balance can be upset, by the operation of a clothes dryer, furnace, bathroom fan, range exhaust, etc. Now let's say we are running right on the ragged edge of adequate combustion air, the baro damper opens and additionally drafts combustion air out of the house. Now, we've created a negative pressure within the house, through the baro damper. .. fire dies down, draft dies down, CO enters negative pressure space. These various scenarios are concerns of safety professionals.

That is an excellent point, however the baro doesn't cause the issue. What you explained is a lack of supply air to feed the fire. Removing the baro to solve it isn't really the right way to fix it. The draft should get its own supply from outside in that case. Then the baro adjusts properly for all the variety of conditions you describe, dryers, fans, etc.

If you have a negative draft from too tight a house with too many exhaust fans, then whether you have a baro or manual damper, the draft will reverse in the chimney, and the fire's fumes will come out of the stove's inlet vents... The baro would leak fumes around the flapper, but the flapper would be shut... The negative draft in the house would reverse the airflow in the stove and pull CO out of the stove through the inlet air controls.

Either way, in a tight house you need an outside air source for combustion. Regardless if you use a baro or a manual damper.

Greg L

Again, as in our discussions in the past, a baro is a safe automatic device that helps control overdraft and pulling too much heat out of a stove. It is difficult to imagine a situation where it is unsafe.
A manual damper requires some experience and expertice to operate safely there are many situations where inattention to this manual device could result in an unsafe situation.

Greg L

LsFarm wrote: It is difficult to imagine a situation where it is unsafe.

Well, It's installation does immediately add a fault into a "sealed chimney system". The other factor being, it definitely reduces the chimney gas temperature.

LsFarm wrote:A manual damper requires some experience and expertice to operate safely there are many situations where inattention to this manual device could result in an unsafe situation.

The only unsafe condition, which I can foresee, would be leaving the MPD open and ending up with an "over firing" situation, of course that baro damper, which we have all come to rely on, would prevent that. I don't believe the MPD takes much more than "common sense and prudence" to operate properly.

all you guys are very smart when it boils down to it!! im so very glad to have people on here who realy care about this sh*t. now I also heard and or read that the inside hight of your stove pipe plays a big factor with the draft as well. my pipe on the inside of my house is fairly tall thats how the installers put it. they did the required hight from the ceiling technique.

bigchunk wrote:all you guys are very smart when it boils down to it!! im so very glad to have people on here who realy care about this sh*t. now I also heard and or read that the inside hight of your stove pipe plays a big factor with the draft as well. my pipe on the inside of my house is fairly tall thats how the installers put it. they did the required hight from the ceiling technique.

Actually, I've always heard inside-stove pipe height/length has more to do with heat gain than draft.

You really gain a _lot_ of your heat from the stove pipe. It _might_ have an effect on draft, but I would think that effect to be minimal, unless you are talking 20 feet of pipe zigzagging around the room before it gets to the thimble.

Quote: Dallas wrote:
'The only unsafe condition, which I can foresee, would be leaving the MPD open and ending up with an "over firing" situation, of course that baro damper, which we have all come to rely on, would prevent that. I don't believe the MPD takes much more than "common sense and prudence" to operate properly.' unquote.

But where is 'common sense and prudence' when you are asleep, the wife and kids asleep, and the MPD is still mostly closed from when you last set it,, just before your last two beers, then you went to bed..

If the stove was really hot, with a fresh load of fuel, and you turned the manual damper way down to control it, then when the fire calmed down, but you were asleep and not there to open it back up... then you have an unsafe situation where the manual damper is restricting the heat flow up the pipe, resulting in a cool chimney, less draft, and a potentially unsafe condition...

If monitored all the time, yes a manual damper has it's purpose, but it is just that: MANUAL.. Not everyone is in tune with their stove, house, the weather... a baro damper is, that is why it was invented and put in use... it is automatic. It takes the human's fail-ability out of the safety equation.

Hey, I have a manual damper on 'Big Bertha' And I use it... but it is outside in an outdoor building, with no occupants except a few field mice... So it can't kill anyone.. I'd never use a manual damper in my residence.. too risky... I have those last two 'beers' too often, then don't have a care in the world for several hours... I don't want those several hours to become eternity.

Manual dampers have their place, mainly to control the flow through a leaky old style stove in a leaky old house with a very strong drafting chimney, and monitored by someone with experience, expertice and doesn't set it wrong before those last few 'beers' and bedtime.

A baro does all the above automaticly... HEY maybe the baro was secretly invented by the booze and beer industry so that people could drink with abandon and live to do it again.

Greg L

I've run stoves with and without baro dampers and I now firmly believe that burning without a barometric damper is "fuelish"
I'm talking coal now, not wood. Once my baro was installed and properly set with a manometer, my coal usage went down slightly and so did my stack temperture, a good thing when burning coal. Alot of former wood burners lke myself, need time to adjust to the thinking about lower stack temps. With wood you gotta keep that stack temp up to limit that nasty creosote. With coal, your just loosing heat and helping Al Gore.