Question about how to set up a trigger.

Hello everyone I am fairly new to this board and have done a search but can’t seem to find exactly what I’m looking for. What I need help doing is setting up a trigger. For example when my son goes to bed our temperature in the house is around 73. We put the A/C on until it hits 70, then we switch it to heat 70 so it doesn’t drop below that in the middle of the night. My question is how can I set it up so that once the A/C hits 70 it triggers the heat to be switched. Any help would be greatly appreciated!!

Hello,

Create a scene to switch the heat and add the Ambient temperature goes below trigger.