In a parallel setup with two centrifugal condenser water pumps, one at max capacity, what is the most likely effect if you throttle back the discharge of the other pump?

• A. No Change in the Total Flow
• B. A Reduction in the Total Flow Rate to the Condenser
• C. A Rise in Pump Power Consumption
• D. An Increase in Condenser Outlet Pressure

Answer: (B)

In a parallel pump setup, the total flow to the condenser is the sum of what each pump delivers at the system head. If one pump is already at its maximum capacity, there’s no extra flow it can provide to compensate. By throttling back the discharge of the other pump, you reduce that pump’s contribution, and with the first pump unable to push more than its max, the overall flow to the condenser drops. So the most likely effect is a reduction in the total flow rate to the condenser. The other options are less predictable or not as directly tied to this scenario.