How to remove heavy soiling? (I got beat by a Rug Doctor)

5. Next my employee uses the stair buffer and a green striped pad on the heavily soiled spots. He says he is “loosening up the dirt” for me. At first I thought this was a little ridiculous, and it wasn’t going to help. But I’m finding that when he doesn’t hit these spots with the stair buffer first, we don’t get the same results. He hits all of the darker areas for a few minutes while I work in another room. Usually after he is done, the carpet is already looking much better. I don’t know if the stair buffer spins faster or just concentrates it’s scrubbing powers more efficiently than the Minuteman… but it works

The stair buffer offers a lot more agitation as it is an osculating head