No Suction on pump

[Masspools]

Hi all

Pentair whisperflo pump 1.5hp 3ph.

New pump installed in commercial facility, trying to prime it and it won't suck in the water. I have no back flow restrictions since the filter valve is on waste. All valves open on the suction side, the pump has suction, I checked the impeller. When I turn off the pump the water flows into the pump from the suction line on front. What could be happening here?
Thanks
James

 

[yeggim]

With 3 phase it's an easy mistake to wire it where the rotation is backwards.

 

[kellyetheredge]

3 phase motors: at the breaker/disconnect swap any of the three wires. Swap 1 and 2, 2 and 3, 3 and 1.......just swap any two to reverse direction in any 3 phase motor. You can also swap any two wires in the "pecker head"; the junction box mounted on the motor.