I was skeptical about using Zep High Traffic Carpet Cleaner in my Electrolux Model 1522 Floor Pro, because the directions state that it should be blotted with a damp cloth or sponge after it has penetrated a stain. So I called Zep's commercial division and asked for the company's recommendation.
I was told that ZEP COMMERCIAL DOES NOT RECOMMEND USING ITS HIGH TRAFFIC CARPET CLEANER IN ANY MACHINE, because it's a potential fire hazard and could otherwise damage a machine. The company insisted that said cleaner is formulated only for spot cleaning by hand.
Zep Commercial used to carry "High-Foam Carpet Shampoo" but has since discontinued it. In case some stores haven't sold all their stock I've posted a photo of the container with the label below.
I've actually been using Kirby Shampoo with satisfactory results in the Floor Pro since it's cheaper than Aerus's Turbo Shampoo, and I can get it at a local Hardware Hank store at a fixed price (Aerus's pricing varies from franchise to franchise). There are other slightly less expensive commercially-formulated dry foam shampoos such as Stain-X and Franklin that are available.
Homemade carpet shampoos may appear to work fine but will likely leave residue and may eventually cause premature wear unless well-rinsed and extracted afterward. It's too risky. Also, it would be more labor-intensive and use more resources if rinsed.

I was told that ZEP COMMERCIAL DOES NOT RECOMMEND USING ITS HIGH TRAFFIC CARPET CLEANER IN ANY MACHINE, because it's a potential fire hazard and could otherwise damage a machine. The company insisted that said cleaner is formulated only for spot cleaning by hand.
Zep Commercial used to carry "High-Foam Carpet Shampoo" but has since discontinued it. In case some stores haven't sold all their stock I've posted a photo of the container with the label below.
I've actually been using Kirby Shampoo with satisfactory results in the Floor Pro since it's cheaper than Aerus's Turbo Shampoo, and I can get it at a local Hardware Hank store at a fixed price (Aerus's pricing varies from franchise to franchise). There are other slightly less expensive commercially-formulated dry foam shampoos such as Stain-X and Franklin that are available.
Homemade carpet shampoos may appear to work fine but will likely leave residue and may eventually cause premature wear unless well-rinsed and extracted afterward. It's too risky. Also, it would be more labor-intensive and use more resources if rinsed.
