What will happen if you start the pump without turning it first?

After long-term shutdown of the pump, the impeller may get stuck due to rust or crystal deposits, and sealing faces may also adhere together. If you start the motor directly without barring the pump, the rotor remains stationary, all the impact force will act on the coupling, bearings and sealing surfaces. This may cause overload tripping in mild cases; in severe cases, it can shear the coupling, damage the seal and destroy the bearings.

The correct procedure is regular hand barring. Check whether the rotation is smooth and free of sticking or abnormal noise. Troubleshoot any abnormalities first and keep the pump on standby properly.