Cleaning Unit (CU)

Cleaning Unit: This is a rough estimate of cleaning power calculated by multiplying PSI and GPM. It’s not a perfect measure, but it can help you compare different pressure washers.

Related terms: cleaning unit, cleaning power

CU, Pressure Washing & Power Washing

CU, or Cleaning Unit, is a term used in the pressure washing and power washing industry to provide a rough estimate of a pressure washer’s cleaning power. It is calculated by multiplying two key factors:

  • PSI (Pounds per Square Inch): This refers to the pressure of the water stream, which determines its ability to remove dirt and grime.
  • GPM (Gallons per Minute): This indicates the volume of water flow, which affects the cleaning speed and coverage area.

Therefore, the formula for CU is:


While not a perfect measure of cleaning power, CU provides a helpful comparison tool between different pressure washer models. A higher CU generally indicates more cleaning power, allowing you to remove tougher stains and clean larger areas faster. However, it’s crucial to consider other factors like nozzle selection and cleaning solutions when evaluating cleaning effectiveness.

Limitations of CU:

  • Does not account for nozzle efficiency: Different nozzles can significantly impact cleaning performance, even with the same CU.
  • Ignores cleaning solution effectiveness: The type and concentration of cleaning solution can greatly influence cleaning results.
  • Focuses on raw power without considering surface type: Applying high CU on delicate surfaces can be detrimental.

Using CU in Practice:

  • Comparing models: When comparing pressure washer models with similar features, CU can help you choose the one with potentially higher cleaning power.
  • Estimating cleaning time: Knowing the CU helps estimate the cleaning time for specific tasks, allowing for better planning and resource allocation.
  • Understanding limitations: While valuable for comparison, CU shouldn’t be the sole factor in choosing a pressure washer. Always consider other factors and specific cleaning needs.

Related Terms:

  • Cleaning power
  • PSI (Pounds per Square Inch)
  • GPM (Gallons per Minute)
  • Nozzle
  • Cleaning solution
  • Pressure washing
  • Power washing

CU serves as a simple yet helpful metric for comparing cleaning power between different pressure washers. While not a definitive measure, it provides valuable information when used alongside other factors and proper cleaning techniques. By understanding its limitations and applications, you can leverage CU effectively when selecting the right pressure washer for your cleaning needs.