Buyers Guide

At West Michigan Power Cleaning Systems, our expert team is committed to helping you find the right power washing solution, no matter what your needs – residential, commercial, agricultural, or transportation.

What’s more, we have an exceptional inventory of merchandise so you can shop on-line or visit our showroom to get an in-house demo from one of our experts. You can try any unit before you buy it! Either way, you will have the benefit of our expert specialization and our commitment to customer service.

Our Buyer’s Guide outlines basic information, technical considerations, and decision guides that might be helpful to you. But most importantly, we invite you to call us, shop with us, or visit our showroom today!

Pressure Washer Basics

Pressure washers (sometimes called power washers) can be used to clean a variety of surfaces including lawn furniture, lawn mowers, vehicles, siding, decks, masonry, sidewalks, concrete floors, industrial equipment and more. Choosing the right pressure washer is important. Using the right pressure washer for the job will give great results in a shorter amount of time using less water than regular cleaning methods with a standard garden hose. Using a pressure washer too powerful for the job could result in damage to the surface being cleaned.

Speaking the Language: Pressure Washer Terminology

Pounds per Square Inch (PSI) refers to the water pressure (or force) produced by the pressure washer. The higher the PSI, the faster the dirt will be loosened from the surface being cleaned. The PSI should be appropriate for the item being cleaned or damage may occur.

Gallons Per Minute (GPM) refers to the water flow rate or the volume of water directed at the surface being cleaned. Look for a good combination of PSI and GPM to deliver cleaning power. High pressure with little water flow is not effective.

Cleaning Power Units (CPU) is a calculation used to compare the cleaning ability of pressure washers. CPU is calculated by multiplying the washer’s maximum PSI by its GPM (PSI x GPM = CPU). A pressure washer with a higher CPU will clean more efficiently.

Ground Fault Interrupter (GFI or GFCI) is a safety device on electric appliances that are typically used near water that protects against electrocution.

Water Pumps (plunger or axial) pressurize the water. Plunger pumps can be repaired and last longer than axial pumps. Plunger pumps with ceramic or ceramic-coated stainless steel plungers will last the longest.

Nozzles control the angle (or fan) of the spray and come in a range of degrees as well as adjustable and rotating types for different cleaning jobs. Spray angles of 40 degrees or more are for general washing. Spray angles of 15 to 25 degrees can strip and wash large areas quickly. A zero-degree (pencil jet) nozzle is great for shooting up high to knock down a bee’s nest or rinse the upper areas of your home but can easily damage soft surfaces, especially wood.

Horse Power - Gasoline engines and electric motors are measured in horsepower (HP). More HP means more power.

How Does a Pressure Washer Work?

A pressure washer takes water supplied from a garden hose and adds pressure using a simple water pump powered by an electric motor or a gas engine. The pressurized water is delivered to the surface by a high-pressure hose, spray gun, and nozzle.

Cleaning with water at high pressure is faster and more efficient because it actually uses less water than cleaning with a standard garden hose. For comparison, a typical garden hose delivers water at about 30 PSI and 10 GPM for a rating of 300 CPU. A light duty electric pressure washer delivers water at 1300 PSI and 1.5 GPM for a rating of 1,950 CPU.

Using detergents or cleaning chemicals can also improve the cleaning ability of a pressure washer. Some models have built-in detergent tanks while others have detergent injector systems that use a hose to draw detergents straight from a gallon jug or 5 gallon pail. Always use detergents that are recommended by the manufacturer to avoid damaging the pressure washer and specific to the surface being cleaned. This is especially true for units with high pressure detergent injection, which means that the detergents are going through the pump vs. low pressure injection, where the detergent is introduced after the pump by venturi (or vacuum).

Can You Select a Pressure Washer on Performance Alone?

No. The first step in choosing a pressure washer is determining how much performance you need to get the job done. How much pressure (PSI)? How much flow (GPM)? Do you need hot or cold water? Is gas or electric better for me? Once you have decided upon these factors you need to choose a product.

Quality is what sets one pressure washer apart from another. Two pressure washers offered by two different manufacturers may have similar performance in terms of pressure and flow but quite different in terms of quality of components and unit configuration. They will also vary in price. When buying a pressure washer selecting the correct performance for the cleaning job at hand is just the first step. The second step is looking at the quality of construction, the quality of the components and whether or not you will have someone to help you if it develops a problem

Selecting a Pressure Washer

Here are some important questions to consider when selecting a pressure washer.

• How often will the pressure washer be used? Helps decide between a residential or commercial model.
• Where will the pressure washer be used? Helps decide whether to get an electric pressure washer or gas pressure washer.
• What will the pressure washer be used for? Helps decide what PSI is needed.
• What conveniences or accessories are desired? Should it have wheels, cord storage, a built-in detergent tank, hose reel? What pressure washer accessories or attachments are available?
• What warranties, repair parts, and service (in my area) are available?

Should I buy a residential model or commercial model?

Residential pressure washers are made for occasional use, typically less than 2 hours per week or 100 hours per year. They are less expensive than commercial models because they are made from different grade parts that are not intended for extensive use. Most homeowner projects can be completed with a residential model, but we strongly encourage you to shop for one that does not utilize plastic pumps heads, hoses or check valves. IT IS VERY IMPORTANT that you check to see if replacement parts are available and affordable. To our knowledge as of this writing, there are no repair parts available for machines made in China. At West Michigan Power Cleaning, we have an excellent selection of Karcher Residential Pressure Washers, the premier brand worldwide.

Commercial pressure washers are intended to handle daily use (100 – 2,000 hours per year). They usually have brass pump heads and stainless steel check valves, and higher PSI and GPM ratings to handle larger cleaning projects and to clean faster. They can be either hot or cold water units.

Heavy duty commercial gas powered machines will use either gear drive or belt drive, with direct drive as a less expensive, less durable option, as the pump will be turning at 3400 RPM, just like the engine. Electric pressure washers can either be direct drive with 1750-1800 RPM motors or belt drive if using a 3,500 RPM motor.

It is important to select a unit with top quality components throughout and not just focus on the engine. Most pressure washer problems are caused by an inferior quality pump. Sometimes customers are “tricked” into thinking a machine has a good pump because it has a quality engine such as a Honda. THAT IS SELDOM THE CASE AT DISCOUNT OR CATALOG STORES! These machines usually have the least expensive pump that they can find, simply to get the price down as low as possible.

If you are going to use a machine 20 hours or more per week look for low RPM, belt driven pumps that are designed for continuous duty use. Stay away from engines that do not have a cast iron cylinder sleeve. Going with a Honda “GX” series or Briggs “Vanguard” series is always a safe bet. For stationary pressure washer systems, a natural gas or propane fired burner system will require much less maintenance than an oil fired burner and you never have to worry about putting fuel into them. In most regions, it is code to require any stationary machine with a burner to be vented to the outside, so there would be ZERO indoor emissions with one of these machines.

West Michigan Power Cleaning Systems has an extensive range of commercial power washers includuing Karcher, Ramteq, and Aaladin. Call us today to discuss your needs. We’ll find the perfect solution!

Do I need a hot water pressure washer or cold water pressure washer?

It depends on what your intended uses will include. Cold water pressure washers (machines that pressurize the water only) can be used to successfully clean many objects and surfaces through a combination of spray impact and the application of detergents. Cold water is generally used where grease and oil are not present, but with the right detergents grease and oil can be effectively dealt with occasionally.

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 faster by loosening dirt, gum, grease and oil. Hot water units use one of 3 means to heat the water. First and most popular are the “oil fired” portable units, using diesel or kerosene as fuel. Next are the gas fired units (NG or LP), which most often equate to a stationary unit and finally there are the very specialized electrically heated machines. These machines are very rare as they are quite expensive, draw at least 48 amps at 480 volts and do not get the water as hot as the other 2 types. Their advantage is that they have ZERO emissions. The down side of heated machines is that they are much heavier, more complex, and more difficult to maintain than a cold water unit.

Electric or gas?

Purchase an Electric Pressure Washer if:

• it will be used indoors or in unventilated areas.
• the areas being cleaned are small (furniture, mower, car, boat).
• an appropriate electrical outlet is accessible.

It is also important to be sure that an electric model has a ground fault interrupter (GFCI) in the plug and you understand what type of electric supply is required (most commercial 120 volt units require a dedicated 20-amp circuit).

Purchase a Gas-powered Pressure Washer if:

• It will always be used outdoors.
• the areas being cleaned are large (driveway, deck, siding on a 2-story house)
• speed is important to you.

How much PSI/CPU is needed for the job?

Light-duty pressure washers provide 1,000 PSI to 1,350 PSI (up to 3,000 CPU).

Best for: cars, light trucks, RVs, motorcycles, bikes, grills, lawn furniture, lawn mowers, boats, brick, gutters, wood fences.

Medium-duty pressure washers provide 1,500 PSI to 2,500 PSI (3,000 to 5,000 CPU).

Best for: driveways, decks, house siding, patios, pools, residential garages, sidewalks, tennis courts, vent/duct cleaning.

Heavy-duty pressure washers provide 2,500 PSI to 4,000 PSI (5,000 to 8,000+ CPU).

Best for: buildings, farm equipment, garages, industrial plants, excavating/landscaping equipment, barn floors, kennels, stripping paint, concrete restoration, tank cleaning.

Cleaning Comparison Chart – Surface Area 10’ x 5’ or approximately 50 square feet.

The chart below illustrates how the difference in operating pressure affects overall cleaning time on three common household surfaces. Times may vary slightly depending on use of detergent, spray distance from cleaning surface, angle of spray and pressure of water.

What is more important – PSI or GPM?

Pressure is good for cleaning, but to rinse you need flow to push the dirt. When purchasing a pressure washer you should consider both the PSI and GPM of the machine. The PSI or pounds per square inch, delivers the "punch" to a washing application and forces the contaminants from the surface. The GPM or gallons per minute, will flush the contaminants from the service. If what you are cleaning comes off easily, but you need to push a lot of dirt -- cleaning animal enclosures or sand from excavating equipment for example -- then you need a high-flow unit. Choosing the right combination of PSI and GPM is the key to purchasing the ideal pressure washing system for your cleaning needs.

Call West Michigan Power Cleaning Systems today! (800) 348-8965