Universal practice test, question 67 of 100

A technician needs to change the oil in a 75-pound R-22 system without pulling the whole system down. What does the rule allow?

• ADraining the oil while the system is still at its operating pressure
• BDraining it into a system receiver taken to 5 psig or lower
• CDraining the oil once the system is below 15 psig
• DAdding nitrogen before draining the oil