Is it true that if centrifugal pump runs in reverse, it will generate zero head?

Question 4: Is it true that if centrifugal pump runs in reverse, it will generate zero head?

Answer: 

             No. As a rule of thumb, a centrifugal pump running in reverse generates approximately half of its rated head. However, such operation is very inefficient, and motor horsepower would be much higher, as compared with half head operation of a pump running at the correct rotation.