Pressure Washer Specs- PSI and GPM
The PSI of your pressure washer matters more than you think. On the low end are pressure washers with a 1,000-2,000 PSI. These washers are good for most typical residential jobs. The next level up are power washers with a PSI of 2100-2900. These can be used for heavier residential purposes, or lighter commercial uses. For professional grade models, power washers with 3000 – 3900 PSI will get most professional jobs done. For tougher jobs, a pressure washer with 4000 PSI may be needed. For industrial purposes, pressure washers with a PSI of 5000 or above are typically used.
PSI isn’t the only rating to look for when deciding on a pressure washer. The Gallons Per Minute rating, or GPM, is also important. The higher the GPM, the faster the pressure washer will work. Two pressure washers may have the same PSI, but the one with a higher GPM will get the job done faster. This can save you time, as well as gas or electricity.
The relationship between PSI and GPM is demonstrated through a measurement called Cleaning Units, or CU. This number is found by multiplying the PSI and GPM. A washer with 3000 PSI and a 3 GPM will have a CU of 9,000. A washer with 3,500 PSI and a 2 GPM will only have a CU of 7,000. So the pressure washer with the lower PSI will actually get the job done faster than the pressure washer with a higher PSI.
This is not to say that PSI isn’t an important factor to look at when deciding on the right pressure washer for your needs. It is important, however, to look at all the specs before making your final decision.