Bonnet cleaning is a low-moisture carpet cleaning method that uses a pad attached to a low-speed machine to scrub the carpet. The pad can either be immersed in water, wrung out and then attached to the machine while the carpet is pre-sprayed with cleaning solution. Or, the solution can be applied directly to the pad before putting it on the machine. In either method, dirt is collected on the pad as it moves over the carpet.

Some cleaning professionals prefer bonnet cleaning because it’s easy and inexpensive. However, this method is controversial in the industry because it can leave soil behind in the carpet. Also, the process may flatten and damage carpet fibers.

Carpet manufacturers, especially those who manufacture Olefin carpets, advise against bonnet cleaning. This type of cleaning may actually void some carpet warranties.

If cleaning professionals are going to bonnet clean, it’s best used as interim maintenance between deep cleans.