Bought this thermostat and when installed tested it agains the three other thermostats in my house and it was four degrees off consistently. I contacted Skytech and they said it is normal to be off 2 to 3 degrees. They said I could send it back for calibration. I just received this. I wasn't about to send it back. Now after programming several times, there is a glitch that on Sunday the set temperature is glitchy and continues to run past the set temperature.I like it but it has many problems.