When recovering refrigerant, what is a necessary step involving water?

When recovering refrigerant, ensuring that water is moving is essential because it plays a crucial role in maintaining safety and efficiency during the refrigeration process. The movement of water helps to transfer and dissipate heat effectively. This is particularly important when dealing with refrigerants that can have a high thermal load, as stagnant water can lead to localized overheating and may also pose a risk in terms of pressure build-up if the refrigerant were to leak into stagnant water.

Moving water can help maintain a uniform temperature and prevent the formation of hot spots, ultimately aiding in a more efficient recovery of refrigerant. If the water were to be stagnant, it might not only increase the risk of overheating but could also affect the performance of the recovery system, causing slow recovery rates or ineffective refrigerant collection.

In contrast, the other options do not contribute to the effectiveness or safety of the refrigerant recovery process. For instance, extracting water to save space does not consider the operational implications of using stagnant water. Similarly, removing all water immediately ignores the importance of water in managing heat load during the recovery process.