ASPE Certified in Plumbing Design (CPD) Practice Exam

To determine the head of an ejector pump accurately, it is essential to consider both the static head and the friction head loss that occurs within the piping and fittings. The static head represents the vertical height the pump needs to overcome to move the wastewater from the source to the discharge point. Meanwhile, the friction head accounts for the resistance that the wastewater encounters as it flows through the pipes and fittings, which can significantly affect the performance of the pump.

By adding the static head along with the friction head loss, you arrive at the total dynamic head required for the system. This total head is crucial for selecting the appropriate pump and ensuring it operates efficiently under given system conditions.

In contrast to the other options, such as simply adding pump capacity, lift height, or discharge pipe length, they do not accurately capture the comprehensive assessment of head required for the effective operation of an ejector pump. The focus on both static height and friction loss is what makes this choice the most reliable method for calculating the necessary head for pump performance.