Hi I have Carrier Weathermaker I live in Texas the outside temperature these days is in 90s in daytime I have the thermostat set at 79 it works well during the day but at night when it is below 79 outside the air circulation kicks in and stays on almost all night with a few breaks in between for 5 minutes, I am wondering why it is doing that is this normal or I need to get it checked. Also there is another control panel right on the unit in the attic with settings for aircirculation system what setting should I have on that right now it has 70.

Have your system professionally checked as some component sounds like it's gone or going. This should not happen regardless how hot outside it gets. And seeing as how there has been such high daytime temperatures in your area your unit has been made to work worse than overtime causing any weak components to fail.

Some thermostats have a blower on setting---system run time and room temperature can bring the blower on to try and satisfy room temp with out the a/c running.