What absolute vacuum levels should be achieved before charging a refrigeration system with refrigerant?

To ensure the efficient operation and longevity of a refrigeration system, it is crucial to achieve a proper vacuum level before charging it with refrigerant. Achieving a vacuum level of less than 2000 microns is considered optimal as it helps to remove moisture and non-condensable gases from the system. These contaminants can cause corrosion, reduce thermal efficiency, and lead to system failures.

A vacuum level of less than 2000 microns indicates that the system has been adequately evacuated, helping to minimize the risk of refrigerant contamination. Additionally, this level allows for sufficient moisture removal, which is critical because the presence of water in a refrigeration circuit can lead to ice formation and ultimately harm the compressor.

While lower vacuum levels, such as those indicated by other answer options, may also be theoretically acceptable, focusing on a target of below 2000 microns is a widely accepted industry guideline that balances effectiveness and practicality. Therefore, achieving this specific vacuum level ensures that the system is in an optimal condition before charging, reducing the risks associated with refrigerant leakage and system performance issues.