Cooling
Why Is My AC Blowing Warm Air?
The usual reasons an air conditioner blows warm air, quick things to check, and when it's time for a technician.
Thermostat settings
Confirm it's set to COOL, not HEAT or FAN, and the set temperature is below the room temperature.
Dirty filter or frozen coil
Restricted airflow can make the indoor coil freeze into a block of ice. When that happens, little to no cool air gets through. Turn the system off, set the fan to ON to thaw it, and replace the filter.
Outdoor unit isn't running
Go outside and check if the condenser fan is spinning. If it's not, check the outdoor disconnect and breaker. A failed capacitor or contactor is a very common summer repair.
Dirty condenser coil or low refrigerant
Cottonwood, grass clippings, and dirt can cover the outdoor coil so it can't release heat. A low refrigerant charge means there's a leak somewhere — refrigerant doesn't get used up, so it needs to be found and repaired by a licensed tech.