Vinegar can be used to clean some carpets depending on the carpet fiber and type of vinegar used.
Know Your Carpet Fibers
Most carpets today are made from synthetic or synthetic blends most commonly, nylon, polyester, acrylic, and wool. It is important to note what fibers your carpet is made from before using vinegar as acetic acid can damage certain fibers such as cotton, acetate, rayon, and silk.
Pet Stains: Vinegar can help to remove pet stains as well as pet odor.
Glue: Vinegar is the perfect stain remover for glue. In this application use white vinegar full strength and let it sit on the hardened glue until it softens.
General Stain Remover: Use equal parts of vinegar and water on a variety of stains.
It should be noted that general household white vinegar should be used in any homemade cleaning solution requiring the addition of vinegar. Household vinegar contains about five percent acetic acid. There are other solutions on the market that contain much higher concentrations, which would greatly alter desired results.