I bought a used 3155 setup and have tried to install it without much success. The controller is calling for water but the green light on the controller is in the level mode. Along with this it (pump) ran with the water well over the float valve until the reservoir was empty! (glad i only had 4 gal in it!). The sensor is clean, it is/has the pointed tip just into the surface of the water. Any help would be Greatly Appreciated Thanks, Hutch