What does a manometer primarily measure?

A manometer is a device specifically designed to measure pressure differences by comparing the height of liquid columns. This instrument operates based on the principle of hydrostatic pressure, where the height difference between two columns of liquid is directly proportional to the pressure exerted by the fluid. In a typical manometer, one side is exposed to the pressure being measured, while the other side is open to the atmosphere or connected to another pressure reference point. The difference in the liquid levels indicates the pressure difference.

This functionality makes manometers an essential tool in various applications where precise pressure measurement is required, such as in HVAC systems, laboratories, and many industrial processes. Understanding pressure differences is critical in maintaining system integrity, safety, and efficiency. Other options do not accurately describe the primary function of a manometer, as they relate to measuring temperature, flow rate, or volume instead of pressure.