The low-side test-pressure data-plate value should be used by a technician to determine a safe pressure for:

The low-side test-pressure data-plate value is crucial for determining a safe pressure during leak testing. This value represents the minimum and maximum pressure that the system can safely endure on the low side. When leak testing, it's essential to ensure that the pressure does not exceed these limits to prevent damage to the system.

Using the low-side pressure data ensures that the technician operates within the safe range specified by the manufacturer, thus maintaining system integrity and avoiding potential hazards associated with over-pressurization. The test is meant to identify any leaks in the system, and adhering to these guidelines helps in accurately determining the effectiveness of the seal of the piping and components involved.

While recovering refrigerant, charging the system, or retrofitting may involve pressure considerations, they specifically may rely more heavily on different parameters or upper-side pressures rather than solely on the low-side data-plate value. Such alternative activities often demand a more complex understanding of the entire system's operation rather than this focused aspect of leak testing.