Found easy way to get AC working after replacing batteries died in thermostat

My AC wasn't turning back on after the batteries died in my thermostat, and after reading tons of articles I decided to try some random things myself, and got it working with a pretty easy solution.

(My Thermostat is a digital Honeywell unit)

I pressed the up and down arrows for about 3 seconds, which brought up "Setup 1/0" on the screen, and then pressing the up / down arrows again for 3 seconds exited the menu, and the AC immediately turned back on.

I did move up and down a bit through the menu to look at what options I had, there was some different test and setup options which I have no idea what they do, but thankfully just entering and exiting this menu seemed to get the AC unit to recognize the thermostat.

Hope this helps someone with a quick fix in the future!

 

Welcome to the forums.

The A/C doesn't recognize a battery operated thermostat.
When the batteries went dead you lost the programming.
Selecting cooling and setting the temperature usually puts the thermostat into hold.