What will the pressure of a recovery cylinder that is half full of recovered R-410A at 90 degrees F be in the absence of non-condensables?

To determine the correct pressure of a recovery cylinder that is half full of recovered R-410A at 90 degrees Fahrenheit in the absence of non-condensables, it's important to understand how the pressure of refrigerants behaves under various conditions.

R-410A is a blend of hydrofluorocarbons (HFCs) that is commonly used in air conditioning systems. The pressure of refrigerants is closely tied to their temperature, which is illustrated by pressure-temperature charts. At 90 degrees F, R-410A exhibits a specific saturation pressure that reflects the balance of vapor and liquid in the system.

When a recovery cylinder is half full of liquid refrigerant, there is also a significant amount of vapor above the liquid. The pressure in the cylinder primarily corresponds to the vapor pressure of R-410A at the given temperature. At 90 degrees F, you can refer to a saturation vapor pressure chart specifically for R-410A to find that the expected pressure is approximately 300 psig. This pressure results from the properties of R-410A, where, despite being only half full, the vapor pressure in equilibrium with the liquid results in this higher pressure reading.

As a result, with no non-condensables present to