What should be done before transferring refrigerant to an empty cylinder?

What should be done before transferring refrigerant to an empty cylinder?

• A. The cylinder should be warmed
• B. The cylinder should be evacuated
• C. The cylinder should be filled with nitrogen
• D. The cylinder should be weighed

Answer: (B)

Before transferring refrigerant, the cylinder should be evacuated to remove air and moisture. Creating a vacuum inside the cylinder pulls out humidity and any contaminants, which helps prevent moisture from reacting with the refrigerant, forming acids, or causing corrosion. It also ensures there’s no air that could dilute or contaminate the charge, enabling a safer, more accurate fill. Warming the cylinder isn’t necessary and can be dangerous because it raises internal pressure, increasing the risk of leaks or a rupture. Purging with nitrogen is sometimes used in some workflows, but the essential pre-transfer step described here is to evacuate. Weighing the cylinder is typically done to verify the charge after filling, not as a prep step.

Before transferring refrigerant, the cylinder should be evacuated to remove air and moisture. Creating a vacuum inside the cylinder pulls out humidity and any contaminants, which helps prevent moisture from reacting with the refrigerant, forming acids, or causing corrosion. It also ensures there’s no air that could dilute or contaminate the charge, enabling a safer, more accurate fill.

Warming the cylinder isn’t necessary and can be dangerous because it raises internal pressure, increasing the risk of leaks or a rupture. Purging with nitrogen is sometimes used in some workflows, but the essential pre-transfer step described here is to evacuate. Weighing the cylinder is typically done to verify the charge after filling, not as a prep step.