At room temperature 72 degrees F, what is the non-operating pressure inside a R-410 refrigerant system?

• A. 120 psig
• B. 150 psig
• C. 210 psig
• D. 250 psig

Answer: (C)

The non-operating pressure inside an R-410 refrigerant system at room temperature, which is typically around 72 degrees Fahrenheit, is approximately 210 psig. This value is consistent with the properties of R-410A, a common refrigerant used in HVAC systems.

R-410A operates at higher pressures compared to some other refrigerants, and its pressure-temperature relationship indicates that at 72 degrees F, the pressure should be in the neighborhood of 210 psig for a non-operating system. This is crucial for technicians to understand since accurate pressure readings are essential for diagnosing and servicing HVAC systems safely and effectively.

Other pressures listed, such as 120 psig, 150 psig, and 250 psig, do not align with the expected characteristics of R-410A at this temperature. Recognizing the expected pressure for various refrigerants helps ensure proper service and maintenance of HVAC systems.