At its core, a pressure washer is nothing more than a pump with a nozzle to direct the water. The idea behind it is that high pressure water will clean things better than water coming out of a garden hose at a typical 60 PSI. In practice, pressure washers do remarkably well, not only cleaning off dirt, but peeling off old paint and even removing graffiti.
There is a fundamental difference between a pressure washer and a steam cleaner, although many people confuse them due to their similarities. Steam cleaners have a tank heater to being the water to near boiling temperature, so that it will better dissolve grease. They are intended for use in removing grease from automobile engines and other machinery. A pressure washer doesn't have this capability for heating the water, so it is not effective for cleaning grease off.
Since providing pressurized water is the main purpose of a pressure washer, the pump itself is the most important part. There are three major types of pumps used in pressure washers: wobble, axial and triplex plunger. While all three can produce sufficient pressure, the first two dont last, as the pumps are working at the top end of their pressure capability. This causes them to wear out quickly. Triplex plunger pumps, on the other hand, can handle the pressure without problem.
There are some companies which are manufacturing what are essentially throw away pressure washers which have big name motors and cheap pumps. As the pump is the most important part of the pressure washer, buying one of these units is foolish. Pretty much any motor will work, as long as it has enough power. The motor is not likely to wear out, like the pump is.
Speaking of motors, both electric motors and gas engines are used to provide power to these pressure washers. Either one works well, although the gasoline engine allows you to use the pressure washer in places where electrical power is not available. On the other hand, if the pressure washer is going to sit for long periods of time, that isn't good for a gasoline engine. Youd be better off buying an electric pressure washer in that case.
Most pressure washers have some sort of soap injector which allows you to add soap to the water being pumped through it. This not only expands the use of the pressures washer, allowing it to clean things that need more than just water, but also allows adding chemicals for removal of painted graffiti.
The two most important specifications for any pressure washer are the flow rate, which is stated in gallons per minute (GPM) and the pressure, which is stated in PSI. These two numbers are multiplied together by some manufacturers, to create a number called the cleaning units of the pressure washer. More than anything, this number provides a way of comparing different units to see which provides more overall cleaning power.
Pressures washers come in all sizes, including a number of them which are intended for commercial and industrial use. For this list, we've limited ourselves to smaller units which would be appropriate for consumer use.
This pressure washer from Simpson provides the most cleaning power per dollar of anything I've found. With a triplex pump, coupled to a Honda gas engine, you won't have any quality problems to worry about. Read Full Review
This pressure washer comes equipped with a Honda gasoline engines. Anyone who is familiar with Honda knows that their engines are highly reliable. Please note, this is not a Honda pressure washer with a cheap pump, but rather a Simpson pressure washer with a Honda engine. That means that you dont have to worry about the quality of either the pump or engine. The engine is direct-drive coupled to the triplex pump for simplicity. The pump itself it made with ceramic pistons, which both dissipate heat better and are less affected by it. There is also a thermal relief valve for safety. This unit will pump 2.8 GPM of water at 3200 Psi, making it the most powerful one on this list. It is also equipped with a downstream injection system for cleaners or solvents.
This pressure washer is just a touch smaller than the one from Simpson. Although it has a axial pump, it's designed rugged enough to last. Read Full Review
This pressure washer from Generac is just a little bit smaller than the Simpson that I selected for first place, but its considerably less expensive. Generac builds their own engines to power these pressure washers. The pump and engine are directly coupled and mounted directly over the axle for ease of movement. While it uses an axial pump, it is still rugged and designed to last. The hose connections are easily accessible, without having to kneel on the ground. This unit comes with two detergent bottles, allowing you to continue working while refilling one. The controls are mounted on the handle for ease of operation. They've even included a holder for the cleaning wand.
This is an electric unit, making it run much quieter than the gasoline engine ones. The triplex plunger pump is designed to be rebuildable, making the unit last virtually forever. Read Full Review
The Pressure Pro Eagle EE2015Gg is an electric pressure washer, equipped with a 2 HP, 18 Amp motor. It will provide 2.0 GPM of water at 1,500 PSI. The big advantage of this over the gas powered units is that it is much quieter, allowing it to be used indoors, if needed. The pump itself is a triplex plunger for long life; and it can be rebuilt. There is a thermo sensor to prevent overheating in bypass mode, but no low oil protection. This unit comes with a 5 year warranty for either home or commercial use. The pressure is adjustable and there is a siphon system for chemical injection.
The high efficiency Leeson electric motor in this unit makes it very energy efficient. The pump itself is manufactured by CAT; the same company which is so well known for their heavy equipment. Read Full Review
NorthStar is Northern Tool & Equipments brand. This 1.5 GPM, 2000 PSI pressure washer runs off a Leeson electric motor. The motor is high efficiency, saving energy and the rotor is dynamically balanced for low vibration. The pump itself is a high quality Cat triplex pump with ceramic plungers. The direct drive configuration reduces parts and maintenance. Chemical injection is also included on the unit.
This unit is a little different than the others on the list. First of all, it's a hand carry unit, rather than being cart mounted. It's also durable enough to be considered an industrial pressure washer. Read Full Review
Although this list is for consumer pressure washers, I've included this industrial unit, which can do double-duty as a consumer model. The main reason that it is considered an industrial unit is the durability of the pump. This is a hand carried unit, as opposed to the others we've looked at, which are all mounted on wheeled carts. That makes it more compact for storage but a little harder to use. The unit is powered by a 1.7 HP induction motor and the pump will operate at either 1350 PSI or 1800 PSI as you select. A thermal switch is included to protect the pump from heat damage. A Three foot chemical pickup hose is provided, so that you can put it right into the chemical bottle, rather than having to dump the chemicals into the units tank.