Gallons Per Minute (GPM)

There are two important numbers to note when examining a pressure washer pump; the maximum pressure (PSI) and gallons per minute (GPM). The maximum pressure is just that, the maximum amount of pressure per square in the pump can create with a constant supply of water and an appropriately powered motor. The GPM refers to how much water can pass through the pump per minute. The higher the GPM, the more water flow can be achieved. Water flow is important when applying chemicals, reaching heights, shooting distances, and rinsing times. Typically, professional pressure washers will begin at 4 GPM and 3000 PSI.