I found no problems running the sweep (we call it "devo") while the cover is on, but our cover isn't "loose" like a solar cover would be. My guess, however, is that there wouldn't be a problem even with a solar cover since the sweeper generally stays on the bottom or on the sides. The only issue I could see is if the floating water feed pipe to the sweep moved a loose solar cover around. Perhaps someone with a true solar cover could give you better info.

Richard