I have a Goulds ST51AV Sump Pump installed in a sump pit outside my house. This pump has a vent hole already in the pump. I have been reading that sump pumps should have a weep hole installed in the discharge line between the discharge and the check valve. The check valve was installed slightly above the discharge of the pump and there is about 2 1/2 feet of 1 1/2" pvc above the check valve where a 90 takes it out of the sump pit.. Is the weep hole in the discharge line necessary when the pump already has a vent hole.