How Much Coal Is Wasted Per Day Through a Barometric Damper?

So by that reasoning, if you open a door(in the house), you have no draft.??? The only way to make the baro stop working is to open the door of the stove, eliminating the need to lower the draft as it is all going through the stove. All the air going in the stove and in the baro has to come in from outside, so why not pipe it directly? I say because the chimney is higher then the entry point of the air, it will still draw air in with a fire going.

Kevin need a beer.......

My speculation is that air from the barometric would satisfy the chimney draft and then also pressurize the stove and flue gas would spill out of your combustion air controls.

Because pressure in the basement is lower than the pressure outside.

I'm ready for one

With due knowledge that I may be the first to send this (my) thread off topic, back about 6 pages or so ago I asked if modern 85% to 87% efficient oil boilers still require barometric dampers. I can now answer this for at least the Energy Kinetics System 2000 series of modern oil boilers. They are 87% efficient and they do not require or use barometric dampers, and they claim that their boilers can save you up to 35% in oil consumption vs. other similarly 85% to 87% efficiency rated oil boilers that may still require the use of barometric dampers.

Just tying up a loose end before this thread fades into oblivion.....

Post By: KLook On: Fri Dec 20, 2013 12:16 pm

So by that reasoning, if you open a door(in the house), you have no draft.??? The only way to make the baro stop working is to open the door of the stove, eliminating the need to lower the draft as it is all going through the stove. All the air going in the stove and in the baro has to come in from outside, so why not pipe it directly? I say because the chimney is higher then the entry point of the air, it will still draw air in with a fire going.

Kevin need a beer....... "

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Yes, you still have draft. In fact the draft should increase, because your letting in more volume (less resistance to flow) of colder, denser, heavier air increasing the air pressure supplied to both the stove and the baro.

But, by just opening a door, that shouldn't throw off the baro's affect on the stove, because the open door affects both the stove and the baro the same.

If one ignores the view that "the hot gases in a chimney pull" (they don't they get pushed) and just remember that cold air is heavy and flue gases and warm air are lighter. Then it gets easier to "figger' it out".

It's kinda like mechanics verses carburetor engineers. Mechanics use the term "vacuum" to describe what makes an internal combustion intake system work (even some old time engine design engineers wrongly used "suction valve" instead of the more correct "intake valve") . However, carb engineers know that vacuum is nothing and that it's the "pressure drop" and greater force of outside air pressure that makes it work. Not suction from inside !

It's higher air pressure outside the stove and flue that is doing all the work, not lower pressure inside.

Paul

Chimneys work primarily due to the temperature differential between the inside of the chimney and the outside air temp. If you pipe cold outside air into your chimney via the barometric damper, wouldn't that lower the differential in temperatures, and kill the draft?

lsayre wrote:Chimneys work primarily due to the temperature differential between the inside of the chimney and the outside air temp. if you pipe cold outside air into your chimney, wouldn't that lower the differential in temperatures, and kill the draft?

Exactly.

That's why some old stove that are designed for both wood, or coal, include "check drafts" near the pipe flange for use when burning wood. It helps lower the stronger draft wood makes in that same stove.

Paul

Here's another analogy that removes the heat confusion.

Pumping up a flat tire. Does the tire get inflated because of energy of less air inside the tire (the tire sucks air?) ? Or, because of the pump's energy (work) is increasing the air pressure inside the tire ?

Paul

lsayre wrote:Chimneys work primarily due to the temperature differential between the inside of the chimney and the outside air temp. If you pipe cold outside air into your chimney via the barometric damper, wouldn't that lower the differential in temperatures, and kill the draft?

Right. As draft declined in the chimney the barometric door closes. But with a sealed pipe to the barometric from outside; since pressure in the basement is lower than outside, the barometric door would stay open and feed air into the stove trying to make its way to the basement.

EKS2000 is a condensing oil boiler. I don't think any condensing oil boilers require a barometric damper.

Carbon12 wrote:EKS2000 is a condensing oil boiler. I don't think any condensing oil boilers require a barometric damper.

I thought this boiler was the most efficient of the non-condensing oil boilers. The efficiency limit for non-condensing is 87%. There are a few condensing oil boilers in the 94% efficiency range.

What woud happen if you piped outside air directly to the barometric damper, but left an open gap of say 5 - 6 inches between the pipe and the damper, so the damper could feel the rooms pressure, but also draw somewhat from outside air?

lsayre wrote:What woud happen if you piped outside air directly to the barometric damper, but left an open gap of say 5 - 6 inches between the pipe and the damper, so the damper could feel the rooms pressure, but also draw somewhat from outside air?

You may cool the chimney to much to maintain a draft.

Flyer5 wrote:

lsayre wrote:What woud happen if you piped outside air directly to the barometric damper, but left an open gap of say 5 - 6 inches between the pipe and the damper, so the damper could feel the rooms pressure, but also draw somewhat from outside air?

You may cool the chimney to much to maintain a draft.

That was my thought also!

I believe it would make warm air at the ceiling ven, out easier since the neutral pressure plane would either stay where it is OR move to a lower position in the house.

There would be no way to regulate the amount of air coming in, in front of the barometric exactly to what it is taking.

I don't think it would kill the draft since the barometric will only take what it needs.