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Training my sense of CO2 ppm

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Re: Training my sense of CO2 ppm

#11

Post by rootusrootus »

CoastalCoder wrote: post #7

I think the elephant in the room is calibration of the CO2 detector. When I looked into this a few years ago, I couldn't find any accuracy guaranties for CO2 meters marketed for households / greenhouses. The closest thing I could find were laboratories that could test CO2 meters in chambers with known CO2 concentrations. But IIRC the pricing for those labs was prohibitively expensive. - There were literally no guaran…

The Aranet 4 claims it can measure up to 5000 ppm with +-3% accuracy. But you'd have to take their word for it, I guess. For $250 I'm hoping it's not a crap sensor.

Re: Training my sense of CO2 ppm

#12

Post by macNchz »

I've had an Awair monitor for a few years and enjoy keeping a fairly close eye on the numbers, but from what I've experienced so far I'm convinced sure I'd be able to train myself to discern CO2 levels. If anything it has mostly just encouraged me to open the windows, even just for a bit, whenever possible, and to always use the kitchen exhaust fan with our gas stove (and motivated me to buy an induction range in the future).

Re: Training my sense of CO2 ppm

#13

Post by kadoban »

CoastalCoder wrote: post #10
kadoban wrote: post #5

Is there any kind of CO2 scrubbing that's at all practical for home? I'm curious what the effects would be of going below ambient/outdoor levels, especially since those are rising (if slowly).

From some (personal) research I did several years ago, I think good ventilation is by far the biggest concern. A well-sealed, occupied room can build up significant CO2 levels pretty quickly. In my particular case, one person, not exercising, could bring CO2 above 800ppm (reported) in just a few hours. So I think lack of ventilation causes way, way more excess CO2 than is caused by recent increases in atmospheric CO2…

My issue with that is that in the summer, ventilation is ~impossible. It's 110 degrees out there, reasonable ventilation would mean either burning out my A/C or living with temps that are far too high.

Re: Training my sense of CO2 ppm

#14

Post by CoastalCoder »

kadoban wrote: post #13
CoastalCoder wrote: post #10

Earlier quoted context omitted.

From some (personal) research I did several years ago, I think good ventilation is by far the biggest concern. A well-sealed, occupied room can build up significant CO2 levels pretty quickly. In my particular case, one person, not exercising, could bring CO2 above 800ppm (reported) in just a few hours. So I think lack of ventilation causes way, way more excess CO2 than is caused by recent increases in atmospheric CO2…

My issue with that is that in the summer, ventilation is ~impossible. It's 110 degrees out there, reasonable ventilation would mean either burning out my A/C or living with temps that are far too high.

Interesting problem. Mind sharing roughly where that is?

Re: Training my sense of CO2 ppm

#16

Post by [deleted] »

kadoban wrote: post #13
CoastalCoder wrote: post #10

Earlier quoted context omitted.

From some (personal) research I did several years ago, I think good ventilation is by far the biggest concern. A well-sealed, occupied room can build up significant CO2 levels pretty quickly. In my particular case, one person, not exercising, could bring CO2 above 800ppm (reported) in just a few hours. So I think lack of ventilation causes way, way more excess CO2 than is caused by recent increases in atmospheric CO2…

My issue with that is that in the summer, ventilation is ~impossible. It's 110 degrees out there, reasonable ventilation would mean either burning out my A/C or living with temps that are far too high.

[deleted]

Re: Training my sense of CO2 ppm

#17

Post by Retric »

kadoban wrote: post #13
CoastalCoder wrote: post #10

Earlier quoted context omitted.

From some (personal) research I did several years ago, I think good ventilation is by far the biggest concern. A well-sealed, occupied room can build up significant CO2 levels pretty quickly. In my particular case, one person, not exercising, could bring CO2 above 800ppm (reported) in just a few hours. So I think lack of ventilation causes way, way more excess CO2 than is caused by recent increases in atmospheric CO2…

My issue with that is that in the summer, ventilation is ~impossible. It's 110 degrees out there, reasonable ventilation would mean either burning out my A/C or living with temps that are far too high.

Simplest solution is a high efficiency air to air heat exchanger to let you circulate a lot of outside air. They are less efficient when dealing with high humidity, but you can have this as part of your HVAC system and never really think about it.

https://en.wikipedia.org/wiki/Heat_recovery_ventilation

Re: Training my sense of CO2 ppm

#18

Post by kadoban »

CoastalCoder wrote: post #14
kadoban wrote: post #13

Earlier quoted context omitted.

My issue with that is that in the summer, ventilation is ~impossible. It's 110 degrees out there, reasonable ventilation would mean either burning out my A/C or living with temps that are far too high.

Interesting problem. Mind sharing roughly where that is?

Ah, yeah, Phoenix summers. I believe parts of Texas and some other places are somewhat similar.

In the winter the situation is _much_ better, but probably 4 months out of the year, the outdoors are unlivable.

Re: Training my sense of CO2 ppm

#19

Post by danans »

kadoban wrote: post #5

Is there any kind of CO2 scrubbing that's at all practical for home? I'm curious what the effects would be of going below ambient/outdoor levels, especially since those are rising (if slowly).

> Is there any kind of CO2 scrubbing that's at all practical for home?

Not scrubbing in the way that a power plant does, but you can improve ventilation, but you probably need to do more than crack a window.

Options from cheapest to most expensive (in upfront cost):

1. Run your stove extractor fan (assuming it is externally vented), and open the window that is furthest from it in the house.

2. Open 2 windows and put a fan in 1 facing out, and if it's winter, wear a sweater.

3. Install a whole house ventilation fan (i.e. Panasonic Whisper Green fan) and keep the furthest away window slightly cracked.

All of the above will cost less upfront but will result in a significant increase in your heating/cooling energy use during hot/cold seasons. If you want to minimize the increase to your heating/cooling energy use, then you need to spend more upfront and:

4. Install a whole house -recovery-ventilation system. This system brings in fresh air 24/7 while transferring much of the heat/"cold" from the conditioned space to the fresh air from outdoors.

What all of these solutions share is that they don't rely on wind/convection to ventilate the house, they are all mechanical.

Re: Training my sense of CO2 ppm

#20

Post by kadoban »

Retric wrote: post #17
kadoban wrote: post #13

Earlier quoted context omitted.

My issue with that is that in the summer, ventilation is ~impossible. It's 110 degrees out there, reasonable ventilation would mean either burning out my A/C or living with temps that are far too high.

Simplest solution is a high efficiency air to air heat exchanger to let you circulate a lot of outside air. They are less efficient when dealing with high humidity, but you can have this as part of your HVAC system and never really think about it. https://en.wikipedia.org/wiki/Heat_recovery_ventilation

Interesting, I don't think I knew that was an option. I'll look into it, thanks.

I rent right now, which means I doubt I can, but hoping to buy soonish.

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