Quote:
Originally Posted by Daox
How is this project coming along? I've been awol lately and haven't been able to keep up!
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Welcome back. Were you warming yourself on some sunny shore?
The project is going pretty good.
The CO2 sensor has occasionally exhibited some anomalous behavior, like cruising along at 700 ppm and then pegging itself at around 6000 ppm. The other CO2 sensors I have aren't exhibiting this odd behavior. It could be a bad sensor, or it could be an artifact that is only present in the analog mode. I have some information that should enable me to get the sensor working in digital mode, but I'll need help.
I also don't have so much confidence in the humidity/temp sensor that I bought. So I bought a precision Swiss sensor which is laying on my desk awaiting installation.
I also ordered a 24v switcher power supply (has arrived), and also a DC to DC step down circuit (not yet in) so that I can power the Teensy and the CO2 sensor and the fans all off of the same supply.
The LCD display is working just great, and has a subtle green back light that is tied to the PWM, so when the CO2 level goes high, the fans run faster AND the display glows brighter. All very satisfying.
In the meantime, I learned a great deal about the CO2 situation in my living room. I also learned that my gas appliances are all introducing CO2 into my house. No problem in the summer, but winter is another story.
Because of the CO2 increases in my house, I am giving a very serious look at induction cooking as an alternative to gas cooking. I'm not even considering electric resistance cooking, I really don't like it. I have gained some interesting information about induction cooking through research and now through experience, which I will share on the
Induction Cooking Efficiency thread I started previously. The cost analysis I did before is still holding up, but when I started considering indoor air pollution, and the need to dump all that air, I have reconsidered.
It's interesting how you can't always predict where something will lead you. When I started out to build a smart HRV, I really didn't anticipate the other changes that would follow.
Stay tuned.
-AC