What is the indoor temperature? Here I compare my thermostat with a temperature probe on my multimeter and two indoor/outdoor thermometers. They've all had 5 minutes to stabilize.
@peterquirk Out of curiosity What temperature range does each have?
@peterquirk Not dragging out a calculator but those error bars don't seem to directly account for the discrepancy in the image. Did they ever settle on the same reading?
@b4cks4w I added the upstairs thermostat for a comparison. After letting it settle for 15 minutes, here's how the five devices read on the kitchen counter.
@peterquirk interesting. Whatcha think, the sensors are not equally good, the sensors are more/less thermally insulated (interior/exterior to device), the averaging algorithms are very different... all of the above.
@b4cks4w The temperature probe has a K-type thermocouple. The rest are unknown. There are many kinds of thermocouples with different linearities in the room temperature range.
https://thermalprocessing.com/using-the-correct-thermocouple/
@b4cks4w Thre Acurite indoor-outdoor thermometer is rated at -40F/-40C to 158F/70C outdoor and 32F/0C to 122F/50C indoor.
The temperature probe is rated at -4F/-20C to 1832F/1000C. Accuracy is +/-1% below 400C, +/- 1.5% above 400C.
The Honeywell thermostat doesn't have published specs and the Radio Shack thermometer is so old I wouldn't know where to find the specs.