How to Choose a Pressure Washer

The Basics

A pressure washer, simply stated, is a power tool comprised of a power source and pump which pushes water through a hose, primarily for the purpose of cleaning a surface. The power source turns the crankshaft of the pump which results in flow of Volume for which it is rated.  The pressure (pounds per square inch) is created when the volume (gallons per minute) is restricted after exiting the pump (Down Stream). The most common method to restrict flow of water is a Spray Nozzle at the end of the wand.

  • Engine drives Volume (gpm) through pump
  • Restriction to flow of Volume creates Pressure (psi)

In deciding on the right pressure washer for you, think of the Volume as rinsing action and Pressure as cleaning action. The higher the pressure, the higher the “cutting” action on the cleaning surface. The higher the volume, the faster the rinsing action. In choosing the right pressure washer for your jobsites, consideration in balancing these two factors is important. In addition, Heated Water enhances the effectiveness and efficiency of the cleaning job. Heat is very useful when cleaning greasy, oily surfaces. It is also most effective in sanitizing food prep, School lunch tables and locker rooms. In short it adds to the Speed and Quality of Clean.

  • Volume = Rinsing Action
  • Pressure = Cutting Action
  • Heat = Quality of Clean

One of the many value enhancing features of this particular tool is the ease in which volume and pressure can be adjusted. Pressure can be adjusted with a simple change of spray nozzle.  If you want to change the volume as well, if using an internal combustible engine, reducing the speed of the engine by adjusting the throttle does the trick. Some sources recommend adjusting the Unloader Valve to change pressure. Under most circumstances, we strongly advise AGAINST using the Unloader Valve as a pressure adjustment valve. Adjustments to the unloader valve will affect pressure, but it is also a SAFETY valve and CONTROL valve – the Heart of the pressure washer. If not set properly, the system may be subject to excessive spike pressures and early failure of the valve, causing damage to the pump.

  • Adjust Pressure with Nozzle Changes
  • Adjust Volume with Engine Throttle Changes (Cold Water ONLY)
  • Unloader is a Safety and Control Valve, Set by Trained Technician
  • Using Unloader Valve to adjust pressure may cause damage to pump

As with any power tool, always put SAFETY FIRST. Proper safety gear and procedures to protect Ears, Eyes and Body are an absolute requirement. Preventative Maintenance to ensure good working order of the equipment and careful use increases profitability. In using the tool, FINESSE is KEY – start with lower pressures and build up. Start at a distance from surface, gradually bring wand closer to surface to be cleaned.

  • Safety First – Proper Safety Gear, Use and Maintenance of Equipment
  • Finesse is Key – do the job right the first time
  • Practice with Caution and Care

What’s Different About Our Pressure Washers

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Cold Water Gas Engine Driven

Cold Water Diesel Engine Driven

Hot Water Gas Engine Driven

Hot Water Diesel Engine Driven

Cold Water Electric Driven

Hot Water Electric Driven, Diesel Fired

Hot Water Electric Driven, LP or NG Fired