Ironically yesterday my wife and a reader had the same question on the exact same day prompting this really quick post about your ecobee3 and the temperature that it displays.
‘the ecobee is displaying the wrong room temperature no way is it 69 in here right now’
Of course my wife is NEVER wrong on anything, period and in this case she was also not wrong.
Yes the thermostat said 69 and it was not 69 in the room where my thermostat was installed it was actually a ridiculously warm 78. Is my ecobee3 broken? Is the ecobee3 flawed and reporting the wrong temperature? Is the ecobee3 installed in a really bad location?
No to all three.
The ecobee3 is doing exactly what it was designed to do because it has a remote temperature sensor attached to it installed in our bedroom. The bedroom sensor is also set as the control sensor so when I look at my thermostat it is actually displaying my bedroom temperature not the temperature in the rest of my house.
When I walk up to my thermostat it says 69 but it is in fact 78 and that makes perfectly good sense since in my settings I told the ecobee3 to use the bedroom temperature to control the ecobee. So my thermostat is overheating the home to try to heat a badly ducted bedroom.
Side Note: Clearly I do not want the rest of my house being 78 just so my bedroom can be 78 because that is just ridiculously warm. Remember that the ecobee sensors do not replace proper zoning nor does it correct poor furnace duct work which is my issue ( Read more on this topic : ecobee 3 Remote Sensor Fail )
The other option for the ecobee was to set it so that instead of it looking only at my Bedroom it will do the average between the bedroom and my main floor. That should make our bedroom more comfortable and also stop the crazy overheating that is happening right now.
Now my thermostat is typically reading 71 degrees. My upstairs bedroom is 67-69 degrees and my main floor is around 73 degrees on average. So again my thermostat is NOT showing the temperature at the stat it is showing the average temperature between the bedroom and the mainfloor where my thermostat is installed.
These settings are much more ideal but at times we are still a bit warmer then we would like to be so there is definitely more I can do. Normally the human body can not notice a difference of 2 degrees so ideally I want to try to get my ecobee3 sensors to read within 2 degrees of each other which is tricky since the sensors as cool as they are, do not have magic beans in them. IE it wont replace zoning and can not overcome my horrible duct work which I consistently whine about.
Another thing I could look at is adding more sensors for more temperature averaging. One ecobee3 remote temperature sensor per floor to give a true operative mean temperature across all three floors. The ecobee3 wont try to heat to the worst condition it will simply average all three floors which would certainly work better then any other thermostat I have used.
Moral is simple. ecobee3 = best smart thermostat on the market. Use it right, know how it works and you will likely end up alot more comfortable then you were before.
Update: January 8ths 2013: As of a few days of running my thermostat using temperature averaging my home as a whole is much more comfortable. The mainfloor is 4 to 5 degrees warmer because of it but from a comfort standpoint its much better.