List four controls that are found on the heating and ventilating system ?

1. Thermostat control: Allows users to set the desired temperature for heating or cooling.
2. Fan speed control: Allows users to adjust the speed of the fan to control the airflow in the space.
3. Mode control: Allows users to switch between heating, cooling, and fan-only modes.
4. Timer control: Allows users to set a timer for the system to turn on or off at a specific time.