Which device is used to automatically control refrigerant levels in a system?

The electric float switch is the device specifically designed to automatically control refrigerant levels within a system. This device operates by using a float that rises and falls with the level of the refrigerant. When the refrigerant level goes below a predetermined point, the float drops, and the switch is triggered to turn on a pump or open a valve to introduce more refrigerant into the system. Conversely, when the level is sufficient, the float will rise, and the switch will deactivate, ensuring the system maintains the proper refrigerant levels.

This automated control is crucial for maintaining efficient operation and preventing potential issues like compressor damage due to low refrigerant levels. It directly interacts with the physical level of refrigerant in the system, which distinguishes it from devices like thermostats, pressure switches, or temperature gauges, all of which monitor other factors rather than directly controlling refrigerant levels.