A dry pump can be reused for evacuating a vacuum chamber, but its effectiveness depends on the specific pump design and application. While a 2hp compressor can be repurposed as a vacuum pump by adjusting the inlet and discharge configurations, achieving a good vacuum typically requires specialized equipment like turbo pumps. The performance of the pump is influenced by its seals and cooling methods, which determine the pressure levels it can achieve. Measuring the vacuum with a pressure gauge is recommended to assess its effectiveness. Overall, while repurposing is possible, the quality of the vacuum will vary based on the equipment used.