All of the following steps are taken in starting a centrifugal pump, EXCEPT:

In the operation of centrifugal pumps, there are specific key steps that need to be followed to ensure proper functioning. While opening the suction valve, ensuring that the pump is primed, and checking the power supply are all essential actions taken to start a centrifugal pump, setting the relief valve is not a typical step in that process.

When starting a centrifugal pump, it’s crucial to open the suction valve to allow fluid to enter the pump, ensuring it can effectively create the necessary flow. Ensuring the pump is primed is vital to prevent damage; a pump that is not properly primed will operate dry, which can lead to overheating and failure. Additionally, checking the power supply is necessary to confirm that the pump has the electrical supply needed to operate.

Setting the relief valve, however, pertains more to the safe operation features of the pump rather than its initial starting procedures. The relief valve is typically used to prevent overpressure conditions during operation, but it does not directly relate to the actions required for starting the pump itself. Therefore, this step is not required when initiating the pump, making it the option that does not fit within the starting procedure.