A pump cooling shroud must be installed on the pump when using the pump in a larger than 2" diameter well casing. The cooling shroud isolates the screened suction interconnector and forces water to circulate past the pump motor. If using the pump cooling shroud in a larger than 2" monitoring well, be sure to install the shroud correctly. The set-screws should be anchored to the pump housing, not the screen. The screws are mainly intended to keep the shroud from sliding off the pump. If they are over-torqued, they will impede the rotation of the impellers and guide vanes and inhibit pump performance.