I had a discussion with a friend who is in the HVAC business and me being a normal Joe my answer was different. So, assuming you have already double checked the thermostat where is the first place you might look?

 

Google?

 

My AC unit works fine it was just a question, and I am hoping people will pick one of the two things in the pole lol

 

Most of the time it is outside.

thewird

 

I went thru this last summer ...

Checked the following in order:

Thermostat - If fan turns on, it's good
A/C Fuse
A/C Capacitor
Furnace.

Turns out the A/C activation signal line on the wiring panel in the furnace was disconnected for some reason. Connected it back up and it was up and running again.

 

Fuse. The A/C fuse and a couple of burnt out bulbs are about the only issues I've had with my 7 in 15 years. Knock on wood.

 

I would have guessed the furnace, initially. But last summer I had a similar problem and we called a guy who fixed it with a $100 part on the a/c unit outside. I was prepared to replace the whole system. And in a couple more years, I may have too. But the first sign of weakness was a little part on that rusty unit outside.