 
How to select the right pressure washer
To help you select the right pressure washer, read the following questions and answers:
Is this pressure washer for home use or commercial / industrial use?
Home Use:
If you will only use this pressure washer under 100 hours per year you need only invest in a less expensive pressure washer. This is usually a cold water unit that can be a small gas (2,000 PSI, or 5.5 HP or less) or small electric (1,000 PSI - 1,500 PSI, 15 amps, 110v.).
Market research data shows that the average homeowner will use a pressure washer on average a maximum of 20 hours a year. That works out to about 2 hours a weekend throughout the summer and a couple weekends in the fall and spring. With this in mind, most consumer units sold are designed to last about 250-400 hours and to meet a price point that the consumer will find acceptable. To meet this design criteria the pressure washer manufacturer typically uses cast aluminum heads, plastic parts, and many integrated parts to keep assembly cost down. These less expensive components mean a less expensive price, but make repairs uneconomical. (Commercial and industrial grade units have brass pump heads, steel and brass internal parts). These types of pressure washers are typically available through mass merchants, discount hardware stores and mail order.
The pressure washers we offer for home use, like commercial-grade pressure washer pumps, feature brass pump heads and high-grade components. However, despite the fact that these units are a cut above home units equipped with aluminum heads, they are not as robust as our commercial and industrial lines.
 | Gas cold water pressure washer
for home use |  | Electric cold water pressure washer
for home use |
Commercial and Industrial Use:
If you plan to use this pressure washer for 100 hours to 1,000 hours per year, you need a commercial pressure washer. Commercial pressure washers use brass heads and are much more durable than the consumer line, but do not have capabilities or durability of most industrial pressure washer units. Some commercial grade gas units use direct drive systems to reduce the number of components, and the price of the unit, while others use a belt drive system to improve durability, with a consequent increase in components and price.
Industrial pressure washers are specifically designed for the heavy-duty user (1,000 to 2,000 hours per year) in tough environments. As such they use the best quality components, such as forged brass pump heads and stainless steel valves. These units are designed to operate eight hours per day every day of the week. Our industrial gas machines use gear-drive Honda engines, while our electric pressure washers use either 1600-1800 RPM TEFC (Totally Enclosed Fan Cooled) motors. Remember, it is important to select a unit with top quality components throughout, and not just focus on the power plant. The unloader valve that regulates the pressure causes most pressure washer problems. Yet many people never consider the quality of the unloader when making their buying decision.
 | If you are interested in an economical commercial-grade gas cold water pressure washer click here to see the EconoMax line |
 | For cold water gas pressure washers engineered for durability with belt-driven General pumps and Honda engines on stainless frames click here to see the DuraBelt line. |
 | For industrial grade machines designed to withstand hard use over many years. We offer the Dirt Killer line engineered for high performance, using German-engineered Kränzle pump with a ten year pump head warranty, and Honda gear-drive engines on American style stainless steel frames. |
 | The KränzleUSA line of pressure washers also feature the high tech Kränzle pump, Honda gear-drive engines and 1750 RPM TEFC motors along with convenient state-of-the-art features like built-in hose reels, auto on/off, on European style frames. |
Do I need hot water or cold?
Cold water:
 Cold water pressure washers can be used to successfully clean many objects and surfaces through a combination of impact of the spray and the application of cleaning chemicals and soaps. To maximize the cleaning potential of a cold water pressure washer you should use a rotary nozzle. This effectively doubles the cleaning impact of the pressure washer. No matter what nozzle you use, selection and application of the correct cleaning chemical can make a tremendous difference. Cleaning chemicals are formulated in different ways for different applications. Make sure you are using the best chemical solution for your application.
Josef Kränzle invented the rotary nozzle concept. All Dirt Killer and KränzleUSA cold water units include a spinning Dirt Killer nozzle that has twice the impact of a flat spray nozzle producing a significant increase in cleaning efficiency, thus saving time, money and water.
Hot water:
We know from washing dishes that hot water makes cleaning easier, especially if we are cleaning greases, oils, or petrochemicals. Cold water can only be as effective if the proper cleaning chemicals are also used. Hot water can often make cleaning up to 50% faster by loosening dirt, gum, grease and oil. Hot water units consist of two power systems: the pump-motor to create the high-pressure water, and the burner-coil to heat the stream of pressurized water. The pump-motor can be can be gas or electric powered. The burner-coil system requires electricity to run the burner motor and kerosene or diesel oil to heat the pressurized water in the heavy-duty heating coil. If the hot water unit is electric powered, you use the same electricity to power both the pump-motor as well as the burner-coil. However, you still burn diesel or kerosene for fuel to heat the water. If the unit uses a gas engine to power the pump, you still need electricity to power the burner-coil. So, unless the unit uses a self-contained power source such as a battery or generator, you have to plug the hot water unit into an electrical source. Because of the heating coil and burner system, a hot water unit is significantly heavier, more complex and more difficult to maintain than a cold water unit.
 | All Dirt Killer and KränzleUSA hot water pressure washers use diesel oil for the burner-coil. |
.jpg) | Dirt Killer offers mobile hot water gas units, which power the burner from a battery, and hot water gas units that require an electrical hook-up. |
 | Both Dirt Killer and KränzleUSA offer hot water electric units. |
How much pressure and flow do I need?
Around the house:
To clean around your house, wash your siding, wash your car or clean your deck, you only need 1,500 to 2,000 PSI. If you use a rotary (Dirt Killer) nozzle you can quickly handle even tougher jobs such as mold or mildew removal. For concrete cleaning or to clean barnacles off boat hulls you would be better off with 3,000 PSI.
Commercial and Industrial use:
As a commercial contractor you need at least 2,500 PSI in order to be fully productive. The cleaning impact of pressure can be increased significantly by use of rotary (Dirt Killer) nozzles. These nozzles can effectively cut cleaning time in half. Flow is important for rinsing horizontal surfaces or powering surface cleaning machines. If you are cleaning vertical surfaces, or excess water is a problem, a low flow/high-PSI unit with a rotary nozzle is probably a better solution. This is because Dirt Killer nozzles work better the higher the pressure; increasing the flow does not make a significant difference.
Based upon these factors, a commercial cleaner would want a machine with at least 3,000 PSI and 4 GPM, to be able to handle a wide variety of cleaning problems. Such a machine would produce pressure to clean, and flow to rinse.
For a given amount of horsepower you can only get so much pressure and flow. Before the advent of rotary nozzles, to get more cleaning impact you needed more pressure and more flow. Pressure is good for cleaning, but to rinse you need flow to push the dirt across the horizontal surface. Now with rotary (dirt killer) nozzles, a smaller pressure washer can give you more cleaning impact. If you just need cleaning impact and rinsing action is less important, such as in machinery cleaning or asbestos removal, go with a high-PSI, low-flow unit, such as the Dirt Killer H357 gas unit, or Dirt Killer E340 electric unit, to keep your horsepower and cost factors down. If what you are cleaning comes off easily, but you need to push a lot of dirt -- for cleaning animal enclosures for example -- then you need a high rinsing or high-flow unit with at least 3.5 gallons per minute.
We offer a variety of units to meet these different applications. Consult the specifications for the different units and look at the sample applications given for each type of pressure washer.
Other factors in picking a pressure washer
The first step in picking a pressure washer is determining how much performance you need to get the job done. How much pressure? How much flow? Do you need hot or cold water? Once you have decided upon these factors, discussed in the other sections, you can focus on whether a gas or an electric unit best suits your needs. Either gas engines or electric motors can power a high pressure cleaner by a variety of drive systems. The different combinations have advantages and disadvantages.
Electric powered pressure washers
Electric units are quiet and do not consume fuel, nor do they pollute or put out fumes. The disadvantage of electric units is that the electrical circuits commonly found in a home are rated only for 110 volt, 15 amps and therefore do not provide much power -- about 1.5 HP or about 2,500 cleaning units. Industrial electrical 110-volt circuits are 20 amp, and thus put out about 2 HP of power or about 3,600 cleaning units. To get more power, an electric motor must run on a 220-volt or 440 volt circuit. These types of circuits are only found in industrial settings. On these larger units you can get 5 HP or 7.5 HP pressure washers or 8,000 plus cleaning units.
The three types of gas drive units
Gasoline powered units have the advantage of putting out larger horsepower no matter where you are located. However, the fuel is more expensive, and you have the problem of noise, and fumes - making them impractical to use indoors. Gas units have different types of drive systems.
Direct-drive gas pressure washers
In direct drive systems the pump is connected directly to the engine. So the pump spins at the same speed as the engine -- typically 3,800 RPM. This system has the advantage of being simple, with few moving parts -- therefore less expensive. The disadvantage is by having the pump spin as much as the engine the bearings get more wear and tear, reducing the life span of the pump.
Belt-drive gas pressure washers
Belt-drive units use pulleys and belts to slow the speed of the pump. Where the engine spins at 3,800 RPM the pump will be slowed to 1,400 to 1,900 RPM depending on the pulley and belt set up. This system ensures long pump life because the bearings do not get as much wear and the pump is isolated from the heat of engine, being separated by the belts and pulleys. The disadvantage of this system is there is some loss of efficiency due to the additional friction from the belts and pulleys. Plus there is more maintenance required adjusting the belts. However, all other things being equal the belt drive unit should provide for the longest pump life.
Gear-drive gas pressure washers
Gear-drive systems come in two styles. Some brands,like the Dirt Killer and KränzleUSA lines, use Honda gear-drive engines with a wobble plate pump. Other manufacturers use a standard gas engine with an extra gearing component mounted between the engine and the crankcase pump. Both of these systems reduce pump speed in half by means of the gears. This increases the pump life by saving wear and tear on the bearings. Of the two systems, the Dirt Killer and KränzleUSA system that uses Honda gear-drive engines with the wobble plate pump is the most efficient and durable for the following reasons. 1) It has the fewest moving parts; the gears are part of the Honda engine so there is no extra oil seal between the pump and the separate gear component. 2) The wobble plate system smoothly transfers the power from the engine in one axis, instead of two like a crankcase pump.
The pump life chart is a rough way of comparing the average pump life of the different gas drive systems based upon how much the pump spins over the life of the system. All other things being equal, the slower the pump spins, the longer the pump will last due to bearing life and the wear and tear on internal parts. The way the pump is used and exposing the pump to adverse conditions like running dry, in extended by-pass, freezing, cavitation and insufficient maintenance will significantly affect how long the pump lasts in actual conditions.
Unit accessories and ease of use
Pressure washers sold for home and those sold for commercial and industrial use often vary considerably in the accessories included and how they are set up. Typically a pressure washer sold for home use has the hose, gun-jet, wand and nozzle all attached into one assembly. This causes two problems. First, you can not easily attach other accessories like a rotary nozzle or drain cleaner hose that would make your pressure washer more effective. Secondly, if any one of these components fail, you often have to buy expensive non-common replacements specifically designed for that pressure washer. Sometimes the cost of these components are equal to the original purchase price of the pressure washer.
Commercial and industrial pressure washers use accessories such as the hose, gun-jet, lance, surface cleaner, and nozzles that can be easily connected or removed. This allows you to use other accessories such as a Dirt Killer nozzle, sand blaster, or extended wand. Some pressure washers come equipped with quick couplers. These make attaching the hose, gun-jet and nozzles a snap, but tend to wear out and leak quickly. Pressure washers designed in Europe, such as the KränzleUSA line, use European standard 22MM safety screw couplings. These are more durable and safe but must be screwed together to connect. Dirt Killer, DuraBelt and EconoMax pressure washers use quick couplers throughout. Thus it is easy to change accessories or to replace worn ones without buying the whole hose-gun-jet-nozzle assembly.
When buying a pressure washer, for either home or commercial use, often times the package offered by different manufacturers will vary considerably. Some include an injector to apply chemical or soap, where others require you buy it as an extra. Some brands do not include, in the advertised price, a pressure gauge or unloader valve for adjusting the pressure; you are required to buy these as extras. So, when buying a pressure washer you must check to see what is included for the quoted price. Some of the options to look for are: gauge, adjustable pressure unloader, soap injector, hose, gun-jet, lance, the number of flat tip nozzles, whether the attachments come all connected or with quick or screw couplings, is a rotary (Dirt Killer) nozzle included?
Operator errors that cost you money
All pressure washers are high-maintenance machines. High-pressure water will eventually wear out seals, O-rings, springs, and other parts that make up a high pressure cleaner. As an owner of a pressure washer, no matter the quality, you can expect to replace seals, valves, and O-rings as well as change the oil as part of routine maintenance. However, the most common cause of excessive maintenance cost is operator error.
Problem 1. Running the pressure washer without water
Normally this will destroy the pressure water pump within minutes. This is the case with the pumps used on the EconoMax and DuraBelt lines. The exception is the Kränzle pump used on all Dirt Killer and KränzleUSA lines of pressure washers. This pump can run for at least one hour without water without damaging the pump. On some electric units, like the SS1700, it can run dry for over two hours without damage. For this reason you can start a Dirt Killer or KränzleUSA pressure washer without the water being turned on. This allows for the easy pull start of gas engines since you are not pulling against the water pressure in the pump. An additional benefit is when you are finished you can pump your pressure washer and hoses dry to protect against freezing.
Problem 2. Running the pressure washer in extended by-pass
By-pass is when the pressure washer is on, but you have not pulled the trigger of the gun-jet so the water is re-circulating within the pump. In this state, the water temperature in the pump head builds as time goes on. If you look at the warranty card for most small electric home owner type pressure washers sold, it would state that if you run the unit in by-pass for more than five minutes you void the pump warranty. This is because the heat buildup quickly damages the pump. Therefore, you have the hassle of turning off the pressure washer every time you are not going to be spraying. For commercial units, they overcome this problem by installing a thermal relief valve that dumps water from the pump onto the ground after a few minutes in an effort to cool the pump when left in by-pass too long. This solution is used on some models of the EconoMax and all models of the DuraBelt brands. However, if the thermal relief valve fails, your pump is badly damaged. Dirt Killer and KränzleUSA lines of pressure washers use the Kränzle pump that has a unique design that allows it to run safely in by-pass for over an hour and some models, like the SS1700, for over six hours.
Problem 3. Cavitation
Cavitation is caused by air getting into your pump. The air can damage your pump as it rapidly expands and contracts. The first sign of cavitation is loss of pressure and a hammering noise. The cause of cavitation is lack of water or air getting into the system. For example, your pressure washer is rated for 4.2 gallons per minute (GPM) but the inlet hose only provides 3 GPM, then the pressure washer pump will still try to pump 4.2 GPM. The suction due to the lack of water will pull in air and cause cavitation. A hole in the inlet water hose can also cause cavitation, as the pump will sometimes suck in extra air. The only solution to cavitation is to feed your pump the required amount of water and to make sure there are no leaks in the water inlet system.
Problem 4. Freezing
If you live in a cold climate, and let your pressure washer freeze with water left in the pump from the last use, there is a possibility of damage to the pump. The typical remedy for this is putting anti-freeze in the pump. With the Kränzle pumps, there is another solution. Since the pump will run dry, just let the pump run for a few extra seconds and pump out the excess water. One pump, the Kränzle APG pump is freeze proof; the unit can freeze, be thawed, and sustain no damage.
Problem 5. Lack of lubrication
High-pressure pumps, like gasoline engines, require oil to lubricate the plungers in the backend of the pump opposite the pump head. The forces generated in the pump are substantial, causing friction and heat. The oil is needed to keep the pump parts cool and turning freely. If oil is allowed to leak out, or water gets into the pump oil, the pump parts will overheat and begin to break apart. Always check your oil level and maintain the correct amount and type of oil in the pump to prevent damage.
Quality components and long-term costs
The components different pressure washer manufacturers use vary considerably between those designed for home use and those designed for industrial use. Homeowner type pressure washers often use aluminum pump heads and plastic valves. These components do not wear well. For this reason, homeowner type pressure washers have a design life of 250 - 500 hours of use. Industrial and commercial grade pressure washers typically use brass pump heads that do not easily corrode like aluminum and therefore provide thousands of hours of life. The Kränzle pumps used on Dirt Killer and KränzleUSA lines of pressure washers are made of brass, with a 10-year warranty. The Dura-Belt line pressure washers are made of brass with a 5-year warranty.
When buying a pressure washer, many focus almost entirely on the power plant, such as the Honda or Briggs & Stratton engine, without looking at the heart and the brains of the pressure washer - the pump and the unloader valve. Most industrial-grade pressure washer pumps use ceramic plungers. The smooth ceramic forms a good seal with the water seals in the pump head. This type of plunger is used on the Econo-Max and Dura-Belt lines. Unfortunately, ceramic is brittle and subject to thermal shock if the pump is run dry or run too long in by-pass without thermal relief. Kränzle pumps used in the Dirt Killer and KränzleUSA lines use ceramic-coated steel plungers. This design dampens heat build-up problems and prevents thermal shock. The unloader is another key component. More pressure washer failures originate with the unloader than any other component. As the valve that regulates the pressure, this device is subject to constant stress. A high quality unloader is a must. Dirt Killer, DuraBelt and KränzleUSA lines of pressure washers all use Kränzle unloaders. Joseph Kränzle earned a reputation as a manufacturer of the highest quality with the design and production of his unloader three decades ago. Since then, other manufacturers have attempted to copy the design many times, however this standard unloader has never been equaled.
In general, you pay in the beginning -- by buying quality, or you pay in the end -- by paying higher lifetime maintenance costs for a pressure washer unit that has a smaller purchase price. However, what hurts more is when a piece of equipment breaks and you lose productivity. Often the opportunity cost of missed deadlines, idle labor, or damaged reputation is higher than the expense of investing in a higher quality piece of equipment.
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