3 of 4 ecobees registering temperatures 5-10 degrees below actual
I have a house with 2 hvac systems, 1 being a 3 zone, for a total of 4 thermostats. I put 4 smart thermostat premiums in the house because I wanted the feature to turn the system off if a door is left open. All of these devices have been installed over a month. When I first installed the thermostats, one of them was registering 5 -6 degrees below actual. I have validated though through the secondary sensors that came with the unit as well as a hand held thermometer. 1 out of four, no big deal. I adjusted the settings to artificially bump up the temp in that unit 5 degrees. Things work fine. Now, after a couple months, 2 more of my thermostats have the same issue but with an even bigger differential. They are reading 10 degrees too low. Do I just keep manually bumping up the temp in settings? Why are the thermostats so unreliable vs the remote sensors? Has anyone had luck with support sending them new units if theirs are not registering temperatures correctly?