I have a Honeywell TH8000 thermostat. It does not respond to any touches on the screen. I need to change from heat to air conditioning. How can I reset the thermostat to start over?

See the following web site, www.thermostatshop.com/manuals/VisionPro%20Owner%20manual.pdf it explains how to unlock the thermostat.

Your screen is locked upped to save a program, just unlock the screen. Read the manual, it's a must.