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

Agreed.

And while a closed MPD with small holes (like most have) can't close off the flue 100%, therefore those smaller holes would present some flue gas flow restriction to help smooth out draft fluctuations. However, being in a fixed position, an MPD would not be able to respond to and limit the range of fluctuations as well as a baro can. . . . all without risk of any mechanically closing the flue may have in some situations.

Paul

Sunny Boy wrote:So, is there a point in some houses that leakage will switch over from more easily leaking cold air lower in the house, to maxing them out (without a change in pressure drop ) and starting to pull cold air from warm air leakage points up higher in the house (cold then coming in where warm was going out), and how that would affect where that NPP point is ?

Sorry, I'll try that again. The only way cold air could leak in up higher in the house would be to draw air out of the house somewhere. Otherwise we void the rule of Air In = Air Out

OR

We factor in wind effects and things get hairy

Also, this is only my nickles worth of free advice. I'm not claiming to be an expert in any of this lol. These are just deductions that I've come up with after researching pressure planes and applying negative pressure to a cavity that contains one..

Here's something.

If the driving force of air infiltration and stack affects is the weight pressure of that denser cold air outside the house pushing in and lifting the warm air inside (once again, warm air doesn't really have any force of it's own to rise, it's pushed up by heavier cold air). That pressure difference outside should be higher than the warm air pressure inside at the top of the house, thus "plugging" the force pushing warm air out ?????????????

If so, then is the stack affect in a house driven more by cold air infiltration ,or by warm air losing heat that is not leaking out in streams, but being lost by radiating through glass, walls and ceilings, then becoming heavier as it cools down and condenses and sinking to replace warm air from below ?

Then the stove and chimney are all that needs make-up air, right ?

Chicken or the egg ?

Paul

Lee,

"............Also, this is only my nickles worth of free advice. I'm not claiming to be an expert in any of this lol. These are just deductions that I've come up with after researching pressure planes and applying negative pressure to a cavity that contains one.. ............."

It's still fun and interesting to stretch a brain cell, or two, now and then. !!!!

Paul

I think your above proposal nulifies stack effect in the house, which we know does occure. I agree the cool air coming in the at the floor is helping push the warm air up AND also the warmer air is more boyant and lighter so it wants to rise just as equally.

Sunny Boy wrote:It's still fun and interesting to stretch a brain cell, or two, now and then. !!!!

Yes sir, and my brain is reaching critical mass over it too..
Soon there will be a mushroom cloud over where I was once standing...

Jump in the furnace first,....why waste the heat!??!

Lightning wrote:I think your above proposal nulifies stack effect in the house, which we know does occure. I agree the cool air coming in the at the floor is helping push the warm air up AND also the warmer air is more boyant and lighter so it wants to rise just as equally.

True.
And the problems with that is figuring out is it stack affect, or convection, or how much of each depending on how well each place is sealed ?

Without alot of measurements, it's all "by guess and by golly" trying to figure out how much coal is wasted, isn't it ?

Maybe seal off the baro and see what the coal usage is compared to local degree days ?

Mushroom clouds ? Those cold fusion guys can't help ya with that ?
Paul

Here's an air flow calculator. Anyone have one of those pockets annemometers to measure wind speed at your Baro?

http://www.engineering.com/calculators/airflow.htm

Carbon12 wrote:Jump in the furnace first,....why waste the heat!??!

No dancin' with the blue ladies allowed !

Paul

Fred and I are just going to sit back and watch. There will reach a point where someones head will explode and I'll post it on Youtube.

Rev. Larry

Sunny Boy wrote:

Carbon12 wrote:Jump in the furnace first,....why waste the heat!??!

No dancin' with the blue ladies allowed !

Paul

I know right? My wife is already jealous about the hot little number I keep in the basement.

6 inch flex duct 100 feet long with a static pressure of .1 inch WC moves 80 CFM according to one chart I found. That's in a supply duct driven by a blower fan. How much air could a fully open 6 inch Baro move under a slight draft? I wish I has the tools to measure!

Carbon12 wrote:6 inch flex duct 100 feet long with a static pressure of .1 inch WC moves 80 CFM according to one chart I found. That's in a supply duct driven by a blower fan. How much air could a fully open 6 inch Baro move under a slight draft? I wish I has the tools to measure!

Then also it depends on how far open the baro door is open. I think you would need to put an extension pipe on the face of the baro and use a manometer to get velocity, then volume could be accurately determined at a particular moment. And then fluctuation would throw in another monkey. Or would the monkey throw the wrench at the baro? .. I. Don't. know..

blrman07 wrote:Fred and I are just going to sit back and watch. There will reach a point where someones head will explode and I'll post it on Youtube.

Rev. Larry

It's gotten that bad, huh ?

Paul