Why does my unit shut off before the room reaches the set temperature?

The most common cause is a restricition of the air flow going to and coming from the unit. Please check your air filter to see that it is clean and no holes are present. Next, check for anything that would impeede airflow of the unit. This includes curtains around the unit. Leaves blocking the vents on the unit. The best way to check airflow on a unit is to feel the air coming from the air vent and the air passing through the fins on  the unit (also known as the condenser). If the air flow feels weak, please clean your unit thoroughly.