What does a barometer measure?

A barometer measures atmospheric pressure, which is the weight of the air above a given point in the atmosphere. This measurement is crucial in various fields, including meteorology, as changes in atmospheric pressure can indicate weather changes. High pressure often correlates with clear skies and stable weather, while low pressure is typically associated with stormy conditions.

Barometers come in different types, including mercury and aneroid, but they all serve the same fundamental purpose: to quantify the pressure exerted by the atmosphere. Understanding atmospheric pressure is essential for HVAC professionals, as it can affect the performance and efficiency of systems designed to control environmental conditions.

While altitude can be inferred from pressure readings, the primary measurement of a barometer is focused on atmospheric pressure itself, distinguishing its function from that of altimeters. Similarly, vacuum pressure and refrigerant pressure require different tools and methods to measure, such as vacuum gauges and pressure gauges specific to refrigerants. Thus, the focus of a barometer remains firmly on atmospheric pressure.