Controllers for controlling heating, ventilating, air conditioning, and cooling (HVAC) systems are provided. The controllers include graphical user interfaces for user adjustment of system settings. The graphical user interfaces also may be designed to present information that facilitates user understanding of system operations. In certain embodiments, the controllers may allow users to adjust airflow values within a wide range of values. In these embodiments, the graphical user interfaces may include slide bars for adjusting the airflow values.