Interesting indoor temperature data

As a demonstration for my SDI-12 USB adapter, I have a raspberry pi zero-w log temperature from a Decagon (METER group) 5TM soil temperature probe using the adapter. The probe is not buried in soil so it is just sensing the indoor temperature. The sensor is located away from direct sun light, just in case you wonder. Here are two snapshots of the data stream:

https://thingspeak.com/channels/462583

One-day

Multi-day

Except for the daily dip-and-rise combinations (why?), the temperature of my home is rather constant near 21.5 Degree Celsius. That is good to know that there is no issue with my thermostat in stabilizing temperature. So why the daily dip-and-rise combinations? The top graph was from Sunday. Notice two dip-and-rise combinations on the plot instead of one? The lowest points occurred around 2:30pm and 8:30pm but that’s not important. What’s important are when the dips started, around 1pm and 7pm. Those were the times we were cooking! The extra heat from the kitchen must have triggered the thermostat to turn off the heater, which made the room temperature drop before it kicked back in and heated the room back up. Without the heater on, the room drops steadily by 0.3 degC per hour. When heat is turned back on, the heater raises temperature at 0.5 degC per hour. You can also see that we were cooking dinner every night. Who would have thought that by posting room temperature online they are giving up a lot of privacy? 🙂