Consistency...

I now have many temperature sensors around the house... and it is important that they are comparable. So here I outline the steps I have taken to ensure that the sensors yield comparable data.
While I have attempted to cross calibrate my temperature readings I have not yet attempted to cross calibrate my humidity readings (which I really should do, and I will do when time allows).
Calibration 1: On the 21st of September I put all the sensors I had on the kitchen bench and used the calibration options within the various software packages to adjust all the sensors to a single value which seemed to be the central tendency of all the sensors. Calibration 2: Last night I did the same thing, but with some new sensors and I did not bring in the sensors from outside.

November 1 calibration

SensorCalibrated (°C)Raw reading (°C)δ °C
Clerestory23.6024.09-0.49
Mufraj (NE)24.6025.33-0.73
Bedroom Southeast24.6024.87-0.27
Bedroom Northwest24.7024.98-0.28
Bathroom Exhaust Up24.7025.20-0.50
Bathroom Exhaust Down24.7024.85-0.15
Laundry Exhaust24.7025.42-0.72
HRV intake24.7025.69-0.99
HRV outlet24.7025.03-0.33
WaterWall East24.6024.49+0.11
WaterWall West24.6024.72-0.12
WaterWall Air24.7025.13-0.43

September 21 calibration

SensorCalibrated (°C)Raw reading (°C)δ °C
Outdoor23.7023.87-0.17
CubbyHouse23.7023.84-0.14
Kitchen23.7024.23-0.53
Mufraj23.7024.35-0.65
Bedroom North Centre23.7024.24-0.54
*Door Laundry22.3019.86+2.56
*Door Main22.3019.86+2.56
*Study23.7021.41+2.29
*Master22.3020.19+2.11
* these 4 sensors are a lower precision sensor than the others.
Why more sensors?
The HRV (heat recovery ventilation) system has a little app that lets me look at the temperature of the incoming / outgoing air - but I cannot record / save those data as the company does not allow it. The easy solution is to put some sensors in key places.
I struggled to get the water wall temperature sensors doing what I wanted, and after several tries I managed to get the wirelessTag outside tag system - which takes thermocouple input - to work. I took the electronics out of the water proof casing as they are inside, but it means that I can measure the water temperature... and means I have one less electronics system to manage.
What it looks like:

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