CO2 movement

[Soper]

Hello. I'm newbie. And English isn't my native language.
Please help me to settle my problem.
The matter I'm gonna build vent system and i a little confused.
Look at the picture.
Lets take a living room.
Fresh air comes trough windows and mixes with hot air. Most of hot air stays up right under a ceiling. Then cold air right above floor goes through crack between a floor and a door to a kitchen (for example). Then hot air goes to vent on a ceiling.

But lets back to a living room. If in this room is a human he exhale CO2. CO2 is heavier than air so CO2 go down to floor and then with cold air goes to a kitchen as I said above.

So my question is: Why in a kitchen vent in a ceiling ? Why we should lost hot air if CO2 is down right above floor ? Why vent don't placed right above floor ? Can I place vent like that to discard CO2 not a hot air under ceiling without CO2 ?

Thanks.

P.S. Or hot air need to make air move out of house ?

[stevehull]

CO2 is not heavier than air in a house. Tiny air movements stir up the air so that CO2 does not get concentrated.

Steve

[AC_Hacker]

Originally Posted by stevehull

CO2 is not heavier than air in a house. Tiny air movements stir up the air so that CO2 does not get concentrated.

My house is sealed against infiltration better than most, but there is work yet to do.

I built a CO2 measuring device, and I have had it running in my house for a couple of years now. It sits on the far corner of my desk, which faces a window. So, I have become pretty familiar with the way CO2 actually behaves.

Normal outside CO2 levels in my neighborhood normally run about 350 ppm of CO2. My winter indoor CO2 levels, with no external CO2 generator like a gas stove, for instance runs about 450-550 ppm, with no one in the room. The longer I am in my living room, the higher the CO2 goes, sometimes peaking at 850-950 ppm.

If I sit at my desk and work, the CO2 levels can go up to 800-900 ppm, or higher, when the room level is on the 600 ppm range.

If I have a ceiling fan on 'low', gently stirring the air, the buildup that is local to my desk does not happen, and the CO2 local to my desk is the same as the room average.

These experiences have led me to visualize 'CO2 bubbles' forming in still air, around someone who is in the habit of breathing. I never would have seen it this way if I had not actually lived with a functioning CO2 measuring device. If someone who has the habit of breathing, ceases this habit, the Brownian Motion will cause a generally uniform mixture of CO2.

Best,

-AC

[Soper]

Originally Posted by AC_Hacker

I built a CO2 measuring device

Can I read how to make one for myself please?

And how about my questions in the topic .
Thanks for the great experience.

[AC_Hacker]

Originally Posted by Soper

Can I read how to make one for myself please?

I documented every step of the construction process in the thread below:

http://ecorenovator.org/forum/conser...-fans-hrv.html

Best,

-AC

[Soper]

AC_Hacker, thanks a lot and what do you think about vent pipes installing I wrote above?

[AC_Hacker]

Originally Posted by Soper

AC_Hacker, thanks a lot and what do you think about vent pipes installing I wrote above?

Vent pipes?

[ryanwc]

Originally Posted by AC_Hacker

If I sit at my desk and work, the CO2 levels can go up to 800-900 ppm, or higher, when the room level is on the 600 ppm range.

If I have a ceiling fan on 'low', gently stirring the air, the buildup that is local to my desk does not happen, and the CO2 local to my desk is the same as the room average.
-AC

I've found it's useful to read internet news from sources I strongly disagree with. The periodic ranting and hand-waving I do tends to mix my CO2 bubble into the rest of the room.

In fact, this is why people who only read news from sources they agree with are referred to as "living in a bubble."

[Soper]

Originally Posted by AC_Hacker

Vent pipes?

I mean ventiduct (sorry my English)

[Soper]

Originally Posted by ryanwc

The periodic ranting and hand-waving I do tends to mix my CO2 bubble into the rest of the room.

Especially at night CO2 and upper air mix a lot )
Sorry for my sarcasm but it's so obvious they don't.