If you discover that refrigerant B is in a system that previously contained refrigerant A, and A is ozone-depleting, what should you do with the mixture?

• A. Drain the system completely and replace with new refrigerant
• B. Recover the mixture in a separate recovery cylinder
• C. Vent the mixture to the atmosphere
• D. Flush with water

Answer: (B)

The main idea is to prevent release of ozone-depleting refrigerants and handle mixed refrigerants properly. When a system that previously held an ozone-depleting refrigerant ends up with a different refrigerant mixed in, you must recover the refrigerant from the system using a refrigerant recovery machine and store it in a dedicated recovery cylinder. This keeps the hazardous substance from escaping to the atmosphere and avoids contaminating other refrigerants, while allowing the material to be reclaimed or disposed of appropriately. Venting to the atmosphere is illegal for these substances, and flushing with water won’t remove the refrigerants or solve the problem. Draining without recovery would still release refrigerant, so the correct action is to recover the mixture in a separate recovery cylinder.