The 10 Best Electric Pressure Washers
How Pressure Washers Work
Some models also heat water, aiding in the cleaning of petroleum-based products and grease.
Gas-powered washers can double that pressure output, but come with a number of safety concerns.
At the foundation of every pressure washer is a motor. Whether pneumatic, hydraulic, internal combustion-based, or electric, this motor's sole purpose is to drive a high-pressure water pump. From there, water is forced through a hose under pressure, and out through a nozzle, when released by a user-controlled switch.
Most modern pressure washers have switches with a pistol-grip style, which requires the user to pull a trigger built into the washer's handle to release pressurized water.
Advancements in nozzle technology greatly improved the effectiveness of pressure washers. Most nozzles attach directly to the trigger gun, and shape the pattern of the water output. Identifying the correct nozzle for an application is important. For cleaning and stripping a flat surface, a fan nozzle may be appropriate. Other applications may call for a narrow jet (cleaning sidewalk grooves), or lower pressure and higher flow (washing cars).
For washers equipped for use with cleaning chemicals and detergents, there are nozzles that aid in the creation of foam. Some models also heat water, aiding in the cleaning of petroleum-based products and grease.
Electric washers plug into standard outlets, and can be supplied with common tap water. Today, these washers typically output at 2,000 pounds per square inch. Gas-powered washers can double that pressure output, but come with a number of safety concerns.
At the industrial end of the pressure washing spectrum, the highest powered pressure washers can be used to cut metal and concrete. Some industrial pressure washers combine water and sand in a process called sandblasting to remove graffiti and strip and/or resurface concrete. Others are used to remove rubber from airport landing strips. The highest powered washers max out at pressures exceeding 25,000 pounds per square inch.
High Pressure Safety Concerns
Electric pressure washers should be handled carefully, as many can output water and other chemicals at pressures great enough to tear skin and cause serious injury. If a washer is improperly cleaned, particles ejected from the hose can be particularly harmful to those they strike. Washers may also kick up debris at high speeds, which can be hazardous.
The exhaust from gas- and propane-powered washers makes them especially dangerous for use indoors.
The combination of electricity and water is infamously deadly. For that reason, users should wear rubber-soled shoes for insulation and keep the cord away from standing water. If you must employ an extension cord, use only those rated for wet conditions.
Pressure washers cannot properly function without an adequate supply of water. Before purchasing one, make certain the pipe you plan to connect the washer to can provide enough water. If operated without enough water, the pump elements can suffer cavitation damage.
If you are interested in using a cleaning chemical with your washer, first confirm that it is safe for use with the model you own. Misuse of cleaning chemicals can damage the pump. It is also important to choose an output pressure suitable for the job at hand. Using too much pressure can damage surfaces irreparably.
With respect to safety, electric pressure washers have an advantage over their gas-powered counterparts: they produce no exhaust. The exhaust from gas- and propane-powered washers makes them especially dangerous for use indoors.
A Brief History Of Electric Pressure Washers
German Alfred Karcher invented the high-pressure washer in 1950, and is often credited as the father of the modern pressure washer. Karcher's status is disputed by Frank Ofeldt, who claims he invented a steam powered pressure washer decades earlier, in 1927.
Ofeldt discovered the cleaning potential of pressure washing by accident while working on a whisky still. Ofeldt inadvertently forced steam through a narrow hose at high pressure, and witnessed its effect on a grease-laden garage floor. From there, he worked to create the first steam pressure cleaners.
The commercial pressure washing industry took off in the early 1960s when Cat Pumps developed a piston pump that was significantly more durable than those that preceded it, and was capable of pressures up to 1,000 pounds per square inch.
By 1975 standard gas-powered commercial pressure washers boasted water pressures up to 3,000 pounds per square inch.
Karcher's status is disputed by Frank Ofeldt, who claims he invented a steam powered pressure washer decades earlier, in 1927.
The automatic car wash industry used pressure washers in an unrelenting commercial setting that involved harsh temperatures and chemicals. Starting in the early 1980s, technological advances necessitated by the difficult conditions in car washes were incorporated in consumer pressure washers. Chief among those improvements was the ceramic plunger pump, which greatly improved the reliability of pressure washers. The early ceramic pressure pump operated for more than 2,000 hours with little maintenance, a durability record far better than those of its predecessors. The ceramic pump also improved the portability and safety of pressure washers, expanding their potential business applications. Additionally, the ceramic pump made it possible for a pressure washer to be powered by an electric motor.
The first electric washers were limited by the output of the standard household electrical outlet, which could hardly support 1,000 pounds per square inch of pressure. For comparison, similar gas models of the time could reach 3,000 pounds per square inch and beyond. This limitation, along with the United States National Electrical Code, which required all high-pressure washers to have ground fault circuit interrupter plugs, stunted the growth of the electric pressure washer. Adding electrical cords and the mandated breaker switches to pressure washers was costly, and many manufacturers instead chose to focus on gas-powered models.
Innovations like the turbo nozzle, which greatly improved the pressure of electric pressure washers, and the concurrent decrease in the cost of electrical components and increase in the cost of fuel, led to a resurgence in popularity of electric pressure washers. Today they are especially well-respected for their consumer applications and flexibility in household use.