Which end of the filter goes in first?

Both ends of the filter have a rubber sealing gasket going around it.  Because the filter is inserted while the machine is upside down, the end of the filter labeled “top/motor side” is placed label side down into the unit.  To ensure correct placement, one gasket is very close to the inner edge of the end cap, and the other is closer to the center.  The end with the gasket that is closer to the center is the end that goes in farthest from the motor.