Question 40Refrigeration & AC - QMED

The correct answer is B. The gauge capable of measuring vacuums at the micron level for the purpose of proving system dehydration during system evacuation with a vacuum pump, but displays the achieved vacuums at incremental threshold intervals rather than continuously, is the Vacuum Gauge (B) in the illustration GS-RA-37. This type of vacuum gauge is commonly used in HVAC systems to verify proper system evacuation and dehydration prior to charging the system with refrigerant. It displays the achieved vacuum in incremental steps, such as 500 microns, 300 microns, 100 microns, etc., rather than providing a continuous readout. This allows technicians to easily confirm the system has reached the desired level of evacuation without the need for precise measurement. The other gauge options in the illustration are not designed for this specific purpose of measuring micron-level vacuums for system dehydration verification.