THERE IS A BLACK LINE ON THE CARPET BEHIND MY TREADMILL

This is a frequent complaint from residential treadmill owners and it is usually followed by the question, ? What is wrong with my treadmill.?

If that is the only symptom, there is usually nothing wrong with the treadmill. When the treadmill is operating, the walking belt acts like a conveyor belt and transports small particles of dirt and debris that were attached to the bottoms of the users sneakers, wear particles from the sneakers and fine wear of the treadbelt itself to the rear of the treadmill. Then, as the running belt goes around the rear roller or idler roller, that goes across the back of the treadmill, some of that debris falls off and is deposited on the floor and accumulates there over a period of time. This is a normal occurrence . The cure is to vacuum that spot when the line becomes visible. Placing the treadmill on a treadmat (a black vinyl mat designed to fit under a treadmill) can make the line less obvious and easier to clean up.

However, if you have an older treadmill and suddenly have this problem, but never had it before, it could indicate that something is wrong with the treadmill and it should be checked by a qualified technician.