Surprising Carbon Dioxide Levels - Using Recirculate on Long Trips

[Donald]

Get an electric car. There was a recent episode of South Park where two of the characters were trying to commit suicide by sitting in a running car with a hose from the exhaust going through the window. They could not figure out why it was taking to long to die.

 

[Owen Lucas]

Slightly off topic, but you should always have a CO detector in your suitcase.

Way too many examples of people dying, especially in overseas / South American hotels due to poor equipment maintenance / incorrect installation of water heaters, furnaces etc.

$16, it's a no brainer. I have 3 portable ones.

https://www.amazon.com/dp/B0D5CQTVXF?

 

[rstsco]

Gas stove? Gas heat?

Neither. Upstairs bedroom converted to my home office. With the window open, readings in the 400s. Close the window with the door closed and eventually climbs to 1200+. Laptop, external monitor, ceiling fan, and my breathing only thing in the room. Since it's summer, the central air runs often.

 

[Zenon]

It's kind of funny— I just went through this whole ordeal with my house. I was considering EFIS/stucco siding, but some people were telling me it would make my old house too airtight. So, I bought one of those meters, and I found that my house is in the 400-500 range when it’s really windy, and in the 600-900 range with no wind. If I close a door in a bedroom and have 3 people and a dog, within about an hour it would be at 1300.


Basically, I discovered that if you make the house too airtight, you need to install an ERV (Energy Recovery Ventilator) or an HRV (Heat Recovery Ventilator) to bring fresh air into the house without significantly changing the air temperature.


For now, though, I’m sticking with my old aluminum siding. Also I never use the air recirculate on my vehicles because it makes the air feel really "stuffy".

Build tight and ventilate right is the way to go.
My numbers hovered around 600-700 ppm of CO2 with HRV on low rpm. Without HRV, it was in the range of 1500 with a couple of people in the house, not mentioning heavy window condensation in the winter.

 

[fat biker]

I keep 2 CO Alarms in my house. One in my bedroom, one in the living room where I have been known to fall asleep.
Whenever I travel CO and Smoke detectors get packed.

One morning about 2AM combo Smoke/CO alarm in the hall outside my bedroom starts screaming.
My 2 dedicated CO alarms were silent.
I called 911, firemen responded shortly with their sniffer. CO level safe.
Pitched the failed unit, replaced soon after.

 

[slo town]

I read an article the other day about how quickly carbon dioxide levels can climb in a car when recirculating is turned on. Higher levels can lead to headaches, drowsiness, fatigue, and more. Especially not good when on long trips.

My wife and I regularly drive to Wisconsin, driving 18 hours straight through. She's about to embark on a 5k miles' trip on her own, So I bought this CO/CO2 monitor off Amazon. Part of the display flashes green when the CO2 level is less than 700ppm, flash yellow when between 700-1500ppm, and flash red and sound an alarm when over 1500ppm. Playing with it Testing yesterday in my closed-door home office, the CO2 level was close to 1200ppm, so I opened my window and it started dropping some, but stayed above 900. Thinking something must be wrong, I set it outside in the shade, where the level dropped and stayed just over 400, which I read was "normal" for being outside.

I opened all the windows in the house and the levels inside dropped to under 500 after an hour or so, but closed them after the outside temp climbed well past 80. This morning I came upstairs to my office and turned it on. It's currently flashing yellow with a reading of 918 to start my day. Unfortunately, it's still warm outside, so not opening the windows, yet.

She will be taking the monitor with her (I hope she uses it). We've talked about switching off the recirculate once the car cools off to have some fresh air.

I'd never thought about CO2 levels being so high in our home, but here in central Texas, it stays closed up most of the time with the A/C on.

We are constantly warned about, CO levels, but have you checked the CO2 levels where you work, live, and drive?

Thanks for the link. I ordered one yesterday.

Scott

 

[Tom NJ]

Thanks for the link. I ordered one yesterday.

Scott

So did I. In my case I want to monitor the CO2 levels from our ventless propane fireplace so I can know how long to run it in the evening.

 

[JustinH]

It's kind of funny— I just went through this whole ordeal with my house. I was considering EFIS/stucco siding, but some people were telling me it would make my old house too airtight. So, I bought one of those meters, and I found that my house is in the 400-500 range when it’s really windy, and in the 600-900 range with no wind. If I close a door in a bedroom and have 3 people and a dog, within about an hour it would be at 1300.


Basically, I discovered that if you make the house too airtight, you need to install an ERV (Energy Recovery Ventilator) or an HRV (Heat Recovery Ventilator) to bring fresh air into the house without significantly changing the air temperature.


For now, though, I’m sticking with my old aluminum siding. Also I never use the air recirculate on my vehicles because it makes the air feel really "stuffy".

All the new houses I have seen within 10 years have makeup air systems. Mine has a little fan that brings in a little fresh air and dumps it through the return air vent on a schedule. It's only noticeable that its bringing in outdoor air during winter because its bringing in cold air. "Winter" in South Texas not long.

 

[alarmguy]

@rstcso
So you got me hooked and kept thinking about this. Wife gave me a birthday present not long ago and had to be returned so she "owed" me a present. Then this came to mind and since it was a present from her I didnt care much about the cost then on top of it a coupon price. SO did some research and bought this model. It also monitors for other pollutants and I think a barometer however I got it for its desktop look. Certainly not as portable but still can easly be. Anyway, since it's Amazon if I dont like it I can return it. I bought it based on YouTube reviews. The second one in the photo technically is just as well if not more highly reviewed and actually maybe a bit more serious as an instrument in my mind. However I figured I would try the desktop one first.
Oh, it arrives today Friday.

This was originally going to be my first choice below;

Anyway great thread, thanks.

 

[alarmguy]

So did I. In my case I want to monitor the CO2 levels from our ventless propane fireplace so I can know how long to run it in the evening.

That's a great use. We have a vented one but I do have concern for my daughter who recently bought an older home. It had a regular wood burning fireplace. It was converted to natural gas, thing is the chimney was closed off. They think it's great but I am concerned because it looks like something a past homeowner did, so I am unsure how safe the burner is and if it should have been vented or not. Meaning did some homeowner cluelessly put in a burner that should be vented or not.

For our house being new, I like the idea of the sensor because I love all things instruments and will find it interesting. It a "tight" house, and we have propane cooktop and (vented) fireplace. However for the first time of owning a house, I guess new construction standards (?) because the house is tight, actually has an air duct that opens and draws in outside air when the AC/Heat Pump turns on.

Next time we visit my daughter I am going to bring the sensor with me. To see what I look at as a jerry rigged NG fireplace.

 

[FordP3]

Has anyone taken this kind of device on their plane trips and what were the results...of course turn the audible alarm off!

 

[FordP3]

So I heard (on NPR Car Talk) that normal mode does some recirculation and recirculation mode pulls in some fresh air. Neither is 100%.

But there can always be exhaust leaks that can get exhaust into the car but would seem that's more likely when parked with engine running than driving.

That might be true on modern cars but a lot of us have cars with manual recirculate mode and manual controls from the 1990s and before. I guarantee you that on our cars that function does not cycle through like you mention...

 

[Donald]

That might be true on modern cars but a lot of us have cars with manual recirculate mode and manual controls from the 1990s and before. I guarantee you that on our cars that function does not cycle through like you mention...

I was not saying cycle. I was saying in RECIR its (example) 90% recycled air and 10% fresh air. And NORMAL it might be 90% fresh and 10% recycled air.

I am not sure of the percentages. Just it's not 100% recycled air when you set it to RECIR.

 

[Tom NJ]

That's a great use. We have a vented one but I do have concern for my daughter who recently bought an older home. It had a regular wood burning fireplace. It was converted to natural gas, thing is the chimney was closed off. They think it's great but I am concerned because it looks like something a past homeowner did, so I am unsure how safe the burner is and if it should have been vented or not. Meaning did some homeowner cluelessly put in a burner that should be vented or not.

For our house being new, I like the idea of the sensor because I love all things instruments and will find it interesting. It a "tight" house, and we have propane cooktop and (vented) fireplace. However for the first time of owning a house, I guess new construction standards (?) because the house is tight, actually has an air duct that opens and draws in outside air when the AC/Heat Pump turns on.

Next time we visit my daughter I am going to bring the sensor with me. To see what I look at as a jerry rigged NG fireplace.

Our house is so tight that when the furnace kicks on it shuts doors. My new meter is reading 400-410 most of the time, same as atmospheric, but if I breath on it it shoots up over 2,000. I read one should not run a ventless propane fireplace more than two hours at a time, which is what we have been practicing, and now I can test it. We run it for aesthetics more than heat, but it does warm the woogies.

 

[alarmguy]

Our house is so tight that when the furnace kicks on it shuts doors. My new meter is reading 400-410 most of the time, same as atmospheric, but if I breath on it it shoots up over 2,000. I read one should not run a ventless propane fireplace more than two hours at a time, which is what we have been practicing, and now I can test it. We run it for aesthetics more than heat, but it does warm the woogies.

We’re definitely at the upper end. 7:30 PM I just read your message so I went and took a picture.
CO2 at 872

I just unboxed it today and manually calibrated as it by bringing it outdoors, which was around 400 and change

I can’t believe your furnace closes your doors!
We have a gas cooktop so it will be interesting to see how that bumps up when we cook during the week and even though our fireplace is vented, I guess we’ll know if it creates any changes

I too am surprised how responsive they are just like when I took this picture. I held my breath so I didn’t breathe on it.
This was a neat little experiment good post by @rstcso also it was perfect timing for that birthday present from my wife

PS, even though I’m not breathing towards it since I just walked in the room to take the photo it’s up to 886 simply being in the room
Amazing
PS by the time I finished this a few minutes later it’s now up to 939

 

[FZ1]

Sorry I read this thread. I now find it impossible to run recirc in my Camry or close the doors in my home.

 

[alarmguy]

@rstcso
So you got me hooked and kept thinking about this. Wife gave me a birthday present not long ago and had to be returned so she "owed" me a present. Then this came to mind and since it was a present from her I didnt care much about the cost then on top of it a coupon price. SO did some research and bought this model. It also monitors for other pollutants and I think a barometer however I got it for its desktop look. Certainly not as portable but still can easly be. Anyway, since it's Amazon if I dont like it I can return it. I bought it based on YouTube reviews. The second one in the photo technically is just as well if not more highly reviewed and actually maybe a bit more serious as an instrument in my mind. However I figured I would try the desktop one first.
Oh, it arrives today Friday.

View attachment 306693



This was originally going to be my first choice below;
View attachment 306694


Anyway great thread, thanks.

Im replying to my own post. As it says I bought the first one. "Qingping"
It's a Beautiful device, touch screen, multiple functions. BUT I AM RETURNING IT before it's too late. I read the negative reviews and they all repeat what I say above, until it stops working then you are out the money you spent.

It really is sweet but I myself found out that it really can not operate on battery power. After 2+ hours it's dead. Maybe it's meant to stay plugged in and even then, based on some reviews I dont see it lasting a long time. (update, in fairness to the company it states 3 hour standby time on the battery)
Anyway, just want to warn others to read through reviews on Amazon if you are considering it. Also the first half of the book of instructions are in Chinese or Russian? Second half in English but the other uncomfortable feeling is to download the app for it. So I am not.

Its a shame, to repeat beautiful device it you want something that sits on a desk or shelf. I might still consider keeping it for that but I feel to uneasy about it lasting more than a few months and its way too expensive for something that will not. Nice to have Amazon returns! I suspect I am going to go with the SAF one

BTW - I put in in the bedroom last night CO2 was just over 1100 ppm!!
Im shocked how sensitive it is, that part is cool. I just about turn and look at it and the numbers start climbing.

(edit- maybe ill give it a chance for the next week after learning that it is not marketed to be used on battery power) Still, not sure I would have bought it knowing that, it does look pretty though *LOL* I just dont trust, though not required, learning it into my WiFi network when fully disclosed that is goes to mainland China server. Seems like this is used to control other devices in the ecosystem like an air filter.

 

[Capt W]

Higher levels can lead to headaches, drowsiness, fatigue, and more.

My wife and I regularly drive to Wisconsin, driving 18 hours straight through.

Extremely long periods remaining sedentary in a car are themselves causes of headaches, drowsiness, and fatigue.

 

[FordP3]

I'm gunna ask again because I truly think it is an interesting subject. Has anyone had one of these CO2/CO detectors active on a plane trip, what were the readings?!?!?!

 

[alarmguy]

I'm gunna ask again because I truly think it is an interesting subject. Has anyone had one of these CO2/CO detectors active on a plane trip, what were the readings?!?!?!

That would be very interesting for sure. Also crowded public spaces. Bus, train, concert hall...
Never realized how much CO2 humans gave off. Sitting at my desk right now in a room by myself, wife in another room and small dog roaming around.
HVAC heat pump running that also has a fresh air intake on it. Meter is roughly 3 feet away on my desk but Im not facing it and it hitting a high in the 1020 ppm range just now.