Most carpet cleaning pros say they use a range of 100-400 psi for regular carpeting, but some use a psi as high as 500 for standard jobs.

A psi setting of 500-100 psi will provide enough pressure to dislodge any particles that may have seeped inside the carpet fibers. Tough stains require a high psi setting, especially if the stain occurs on a light-coloured carpet.

For professional carpet cleaning results, as a minimum we recommend a pump with at least 100psi water pressure. Coupled with a professional vacuum system (to suck the water back out) you can achieve top class professional results with a 100psi pump. Pumps in the 100psi to 150psi range tend to be diaphragm pumps.

A pressure washer is ideal for cleaning deep dirt and stains out of the rug. The pressure of the water penetrates the rug's surface and forces pollutants, dirt, and debris out of the rug's deepest fibers and draws them to the surface or out of the rug entirely.