A high-pressure appliance containing 210 lbs. of R-407C refrigerant must be evacuated to a level of;

For a high-pressure appliance containing 210 lbs. of R-407C refrigerant, the appropriate evacuation level is critical to ensure the complete removal of refrigerant and any moisture that may be present in the system.

Evacuating to a level of 10 inches of vacuum effectively ensures that the system is adequately free of moisture and non-condensable gases, which is essential for optimal performance and longevity of the system. A vacuum level around this measurement indicates that most of the refrigerant has been removed and that the pressure within the system is sufficiently low to prevent any remaining moisture from boiling, which could lead to acid formation and damage.

This level also exceeds the typical evacuation requirement for such appliances, ensuring a safe operation post-evacuation. It's crucial to maintain this level for a specified duration during the evacuation process to confirm that the proper vacuum is sustained and that no leaks exist.