Refrigeration Plant Operator B Practice Test

Which two checks can verify if charging of a refrigeration system is complete?

1. Recommended weight from the manufacturer and sight glass on the receiver

2. Compressor temperature and pressure readings

3. Electrical current draw and voltage supply

4. Gas leak detection and insulation checks

The correct answer is: Recommended weight from the manufacturer and sight glass on the receiver

The recommended weight from the manufacturer and the sight glass on the receiver are crucial methods for verifying that the charging of a refrigeration system is complete. The manufacturer's recommended weight indicates the precise amount of refrigerant necessary for optimal system performance. When the system is charged with the correct amount, it will operate efficiently and effectively. Additionally, the sight glass on the receiver provides a visual indication of the refrigerant's status. When the system is properly charged, the sight glass should show a clear liquid. If the sight glass is cloudy or has bubbles, it may indicate that the system is undercharged or has issues with refrigerant flow, signaling that charging is not complete. In contrast, the other methods, such as compressor temperature and pressure readings, are more indicative of operational efficiency rather than the completion of charging. While these readings can help diagnose performance issues, they do not directly confirm the refrigerant level. Similarly, checking electrical current draw and voltage supply pertains to the electrical side of operation, not the refrigerant charge. Gas leak detection and insulation checks are focused on system integrity and efficiency rather than the charging process itself. Therefore, the combination of the manufacturer's recommended weight and the sight glass provides the most reliable verification that charging is complete.