My thermostat for the AC/heat pump is a bit more complex than the Honeywell, etc for heat only. You have to select some equipment in the settings that I've never had to touch since the house was new.
This morning, there was a brief power outage, just a minute or so. I happened to see the temperature setting was incorrect so I reset it and forgot about it. As the day wore on, the temperature went up and finally hit the set point to kick on the AC. I heard it go on, but after a few minutes, it was putting out hot air. Played with the touch screen, no go.
I called my son and got the name of an AC guy that lives in our community. I called him, told him the problem and he walked me through the setup menu and said it takes about 10 minutes to reset. Sure enough, it worked.
This is a guy that never heard of me but he helped get me going and did not ask for any payment. So, I scheduled the annual cleaning and checkup. He will be my new service guy.