When procuring an absorption chiller, the most critical factor is the Coefficient of Performance (COP), which measures energy efficiency. For Single-Effect chillers, expect a COP of 0.6-0.7, while Double-Effect chillers should reach 1.2-1.4. You must also verify the heat source compatibility, whether it is waste heat, steam, hot water, or direct-fired gas. Ensure the unit utilizes high-quality corrosion inhibitors (like Lithium Molybdate) and features an automatic purge system to maintain the internal vacuum, which is vital for long-term operational stability.