Where must the pump drain be located?

The correct answer indicates that the pump drain should be located at the lowest part of the pump and the lines. This positioning is crucial because it allows for the effective removal of any accumulated fluids, including water and other substances that may settle due to gravity. When the drain is at the lowest point, it ensures that all liquid can fully exit the system when drained, preventing any residual water from remaining within the pump. This is important for maintenance and operational efficiency, helping to avoid issues such as corrosion or contamination within the pump system. Additionally, proper drainage helps in freezing conditions by ensuring that no water remains in the system that could create ice blockages or damage to pump components.

The other options do not meet these critical functions. For instance, placing the drain at the highest part could lead to trapped liquid, and positioning it in the middle would not facilitate complete drainage. While having the drain accessible for maintenance is important, without proper placement at the lowest point, maintenance won’t be as effective in preventing potential problems.