What aspect does a compound gauge measure?

A compound gauge is specifically designed to measure both positive pressure (above atmospheric pressure) and negative pressure (below atmospheric pressure, or vacuum). This capability makes it essential for various applications in HVAC systems, where monitoring pressure changes is critical for performance and safety.

The gauge typically features two scales: one for measuring pressures above atmospheric pressure and another for measuring pressures below atmospheric pressure. Thus, it provides a complete picture of the pressure conditions within a system, which is vital for diagnosing issues and ensuring efficient operation.

This versatility distinguishes the compound gauge from gauges that are limited to measuring only high or low pressures, or those that measure temperature. Understanding how to utilize a compound gauge effectively is fundamental in the HVAC field as it aids technicians in maintaining and troubleshooting HVAC systems accurately.