I had a new outdoor unit and indoor unit and maple chase thermostat installed in my home a few months ago. Some time last night the a/c stopped working and on the thermostat the green aux light is on while in cool mode and there is hot air blowing out of the vents. It was set at 74 deg and its reading 87 deg and keeps pumping out warm air. I've tried resetting the thermostat but that didn't help. Any ideas?

Check the Breakers and Outside Unit disconnect, and see if the outside unit is working.

Your unit is less than one year old and should still be under warranty. Give the company that did the install a call.