A new sensor...

I'ver splashed out and picked up a pair of Purple Air Flex air quality monitors. These sensors measure temperature, humidity, pressure, PM2.5 concentrations, and total volatile organic compounds (VOC). (The VOC readings are currently experimental.) The sensor outside data are publically viewable on the purple air map, but the inside sensor data is not disclosed in real time. I will however be doing some experiments with it. One of these days I'll find the ideal sensor package, but until then I just keep collecting!

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Temperature (Out vs. Old vs. New)

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I have fielded more than a few questions about the temperature of our passive house versus the temperature of the house that we lived in prior (on the same lot).  So I've used the data I had on hand which is temperature (°C) recorded every 5 minutes over since October 2012. For the sake of consistency I am only using the NetAtmo sensors that I have had for that entire period. So I only have one outside sensor and one inside sensor located in the the respective living room. The outside sensor moved around a bit, but it should be good enough.  I've converted those measurements to hourly averages.  This ends up being ~ 66,955 hours to play with (52,232 hours from the original house, 14,723 hours from the passive house). I've left the rental house out of this comparison, but it was disturbing like the original house despite being ~ 20 years old. The key take-home messages: The passive house a much less variation in temperature than the original house (or outside).  In the summe
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