This is a Heat pump system. A/c light is on thermostat.

Is this a Honeywell thermostat? Usually this means the batteries in the thermostat are bad or it isn't getting power.

Thanks dewey066. It turned out to be a blown fuse on the unit in the attic that blows heat/cold air into the house. Next question is why did it blow? Air filter was clean.

The breaker trips because the load exceeds the rating for the breaker. Usually this happens when the blower motor first starts running. Depending on the type of blower, there are oiler ports on the motor itself. Shut the power off to the unit, open the cover up and find the blower motor (usually it sits inside of the blower wheel). On both sides of the motor, towards the outer edges you will find two small holes (sometimes there is a little plug inside of it (usually yellow or black). Take some 3-in-1 oil and put 3-4 drops into each hole. This should be done every year or two. They sell oiler bottles with a long flexible hose/spout to get into the tight spots. This is easier said then done. Good luck!