After installation, we noticed that the thermostat didn't detect changes in temperature very effectively, and therefore didn't turn on and off as expected. Select the desired mean temperature using "Up" or "Down." The Honeywell 8000 thermostat includes a programmable a screen-lock feature that prevents inadvertent changes of the mean, or desired average, temperature of the household. Press the screen button below the number "2" to lock the screen. If you don't want children and other users to adjust previously saved cooling and heating settings, enabling the security lock can prove very useful. TH8320R1003 fully screen locked forgot pass code. Not sure what type. But when I try to select an option it goes to the lock screen asking for a 4 digit code and its not the day code Not the date code. It's very easy to install and fits the Thermostat perfectly. Since you talk about locking, I guess you are talking about a touch screen thermostat. Get free shipping on qualified Lockable Programmable Thermostats or Buy Online Pick Up in Store today in the Heating, Venting & Cooling department. I bought this thermostat guard to cover our [[ASIN:B000EW80Q0 Honeywell RTH7500D Thermostat]]. The security settings on your Honeywell digital thermostat can be used to prevent unauthorized changes to system settings. HVAC Technician: ... We have a business with a Honeywell thermostat. Option "1" locks all the thermostat functions except for the "Cancel" key and the temperature controls. Option "2" completely locks the thermostat screen. Code "0670" means that you can change the screen lock settings to keep someone from reprogramming the thermostat. Press the "System" key to … When you press the "System" key on this thermostat, five touch keys appear between the "Cancel" key and the "Done" key at the lower center of the screen. Press the screen button below the number "1" on the screen to lock all keys except temperature. Option "0" unlocks the screen. How do I reset this thermostat?