You can use the Rotate (Flip) grip 
to rotate schematic symbols 180 degrees in the direction indicated by the grip.
Rotate (flip) grips on a schematic symbol
When you rotate a schematic symbol that is connected to other objects, the software adjusts the connected objects to maintain their connectivity. For example, the software might make minor adjustments to the lengths of connected schematic line segments after you have flipped a symbol. If it cannot adjust the objects, it disconnects them.
You can also rotate the symbol using the Properties palette if you release the anchor first. However, this method requires that you break the relationship between the symbol and the line. You can restore the relationship by reattaching the symbol with a curve anchor. To rotate an orthographic symbol using the Properties palette, first select the symbol. On the Properties palette, expand Basic, and expand Location. For Rotation, enter the number of degrees and press ESC.