That error 33 means motor control failure. You should call tech support. 1-800-962-9888.

Start by removing the set and rotating the stop **** (the metal tab above the rotor) a few degrees counter clock wise. It should rotate freely in one direction. When you turn the pump on or off, the stop **** should automatically align. If the rotor moves, or you get an error, your pump will need servicing. Otherwise try turning the set valve manually (with a flat head screw driver) to see if it sticks. But most of the time, the valve just isn't loaded properly. Push down on the thumb tab to make sure the set is fully seated and hold it down until you start running the pump. It should lock into place at this time. This also works for the bigger ePumps.