Removing Rust stains from Bricks?

[memphis]

We had an especially warm summer in the South this year, so much so that we went and bought a $100 window unit to help keep the house cooler upstairs. I placed it in the window with zero problems. Problem is now I can see that where the water condensation ran off the window unit and onto the brick exterior its left a rust stain in the brick/morter that looks pretty bad. Any idea's as how to remove the rust stain from the brick and morter?

Thanks

[HayZee518]

the rust or iron oxide can be removed with tsp and water and a scrub brush. after that a pressure water cleaner is the next choice.