Most pressure washer nozzles are colour coded to indicate what pattern (degree) of fan spray they produce. Although colors may vary depending on the manufacturers, described below are what is commonly used as the industry standard.

The red tip is the zero degree nozzles – these pressure washer nozzles produce a pencil point pattern, there is no fan created so this is not the tip to use when cleaning coverage is desired. The red tip does deliver the highest impact as it concentrates the pressure into the smallest area. Avoid damaging wood or other fragile surfaces. This is an ideal tool for cleaning under the deck of a lawnmower, removing caked on mud from equipment, cleaning stains from concrete, masonry, steel and aluminium even removing the grass from cracks in the side walk.

The yellow tip creates a 15 degree fan pattern. These pressure washer nozzles are referred to as chiselling tips. Held at a 45 degree angle you can use it like a scraper to remove peeling paint or mildew. It is also used for other tasks where breaking the bond is harder than average. Of your different pressure washer nozzles, you will find yourself using this one the most often when the task is tough. This is the only situation I know where you’ll find that when the going gets tough the tough gets yellow.

The green tip produces a 25 degree fan pattern. This is a wash tip. These pressure washer nozzles are the ones to use when breaking the bond between the grime and substrate is reasonably easy. These can also be used for sweeping leaves or debris from flat surfaces or curbing. These pressure washer nozzles have the widest variety of applications as the fan degree allows for good impact pressure and cleaning coverage.

The white tip is the 40 degree fan tip. The wider dispersion of the impact pressure limits these pressure washer nozzles to rinsing and delicate washing. These are the tips to use for washing/rinsing glass or washing vehicles. These are great tips for wooden decks and all delicate substrates.

There are three types of pressure washer unloader valves.

• The Trapped Pressure Type
• The Flow Type
• The Compensating Type

The Trapped Pressure Type

Commonly referred to as just “Pressure” type. This type of valve opens to bypass when it senses the pressure build up of the pump output having nowhere to go. The main characteristic of this the most commonly used valve is how it traps the pressure in the hose when the trigger of the pressure gun is released. The disadvantage of this type of valve is the spike of pressure felt by the operator and pressure washer components when the trigger is again squeezed. This creates a “kickback” effect on the gun/wand so be careful when using ladders or other types of access equipment.

The Flow Type

This kind of unloader valve activate the bypass loop when they sense the lessening of flow between the valve and trigger gun. The major characteristic of this valve is that no pressure is trapped in the hose thereby eliminating the pressure spike created by the “trapped pressure” valves. The main disadvantage of the flow type unloader is that you can’t change the pressure by downsizing the orifice size of your nozzles. The valve senses the loss in flow and begins to cycle repeatedly.

The Compensating Type

This kind of unloader valve is the most recent addition to the world of unloaders. The concept is a hybrid between the flow and trapped pressure unloader types. Basically this is a trapped pressure unloader with a compensating feature which radically lessens the pressure spike typically felt with the standard trapped pressure unloader. The main idea behind this unloader is to have the smoothness typical of a flow type unloader without the inherent disadvantages.

Pressure washer unloader valves are the main “safety” in your power washer system. The most commonly used is the “pressure actuated” type valve. When the pressure gun trigger is released the valve senses the pressure build up and like a “traffic cop” it diverts the water flow from the pump outlet back into the inlet side of the pump this is called “bypass mode.” Without this critical component this closed-gun situation would build pressure to the point where it would stall the power source, rupture the gun, hose or even the pump itself.

The most basic function of the unloader is to act as a “traffic cop” to the water flow in your system. Depending on the type of valve it will either sense “pressure build” or “reduction in flow”. Depending on the type, when one of these conditions is met the unloader will then actuate to divert the water flow back to the inlet side of the pressure pump, where it will circulate through the pump back to the inlet side of the valve to the inlet side of the pump again in what is called a bypass loop when this is occurring the pump is said to be in “bypass mode” and the unloader valve is said to be “cycling”. This scenario ends when the trigger is squeezed alerting the unloader valve to redirect the flow to the high pressure nozzle once again. While this may seem to be problem solved it is not without risks. When the water flow is in bypass new cool water is not entering the system. The moving parts in the pump are creating friction which produces heat that is transferred to the water flow in bypass. Since a limited amount of water is in bypass this transfer of heat can occur quickly.

Most pumps are designed to handle water temperatures of 140 F. When the water in bypass reaches 155 deg Fahrenheit damage to the pump will begin. Damage can occur to the pump packings, plungers and seals and even to the short bypass hose in external bypass setups. It is a good idea to have a pump with a thermal relief valve to offer some protection against excessive heat buildup. It is a better idea not to leave a pump in bypass mode for more than 2-3 minutes, by simply squeezing the trigger gun you will introduce new cool water into the system.

Please see the next article for details of types of pressure washer unloader valves.

Generally the gun will have a 3/8? inlet port where the hose is attached and a 1/4? outlet port to the wand/lance (this is when 3/8? pressure hose is used). When the trigger is released the gun is said to be in “closed” position stopping the flow of water. When the trigger is squeezed it is in “open” position directing water to the nozzle once again.

These trigger guns control water flow by means of a spring, ball and seat. The trigger controls the on/off of the water flow. When the trigger is released the ball inside the gun is forced to seal in the seat by the spring and the water flow. This effectively stops the flow of water and sends the unloader valve into bypass mode. When the trigger is again squeezed the flow of water and spring force the ball from the seat and water is once again directed to the high pressure nozzle.

Pressure washer trigger guns are designed for safety. The design of a trigger gun allows it to go to closed position if the operator loses control or drops it. This is the safety mechanism of the trigger gun. Pressure washers, especially that of industrial type can discharge fluid at a whopping 31,000 psi, and if you happen to drop and lose control of a trigger gun, this may have damaging consequences.

There was once a report that a Pressure Washer rental was sued by a renter who claimed he lost control of the gun and was “cut open” from mid-thigh to his chest causing him to be unable to work for an extended period of time. As a result we had 25+ trigger guns impounded as evidence. Investigators later learned that this “roof cleaner” regularly used tennis balls to keep the trigger gun open to avoid the “hand fatigue” that can be caused by squeezing a trigger for an extended period of time. Although today’s pressure washer trigger guns are well designed for safety, don’t negate these safety features by using tennis balls, duct tape or some other method to artificially hold the trigger. Instead look into purchasing an “easy pull” pistol style trigger gun. These are designed to require a much lesser force to pull the trigger than a standard style gun.

Motor (Gasoline, Diesel or Electric)

• Pressure Pump
• Pressure Hose
• Trigger Gun
• Unloader Valve
• Pressure Wand or Lance
• Wand or Lance Tip

THE PRESSURE WASHER MOTOR

Different sorts of motors are used for different types of pressure washers. It may also depend on the type and location of the applications. Most high power washers used in industrial works, commonly use gasoline or diesel motors. Because most industrial cleaning requires great amount of time, these motors could run much longer without overheating compared to their electric counterpart. And since most industrial works are done outdoors; and sometimes or mostly offsite, where there are no available electricity. The ones with electric motors are mostly used for light to moderate washing works (e.g. house, car, and small boats) and are the most excellent used for indoor applications because these motors do not emit harmful fumes.

HIGH PRESSURE PUMP

You’ve now arrived at the “core” of the system, the high pressure pump. All are positive displacement reciprocating pumps either piston or plunger types. Plunger pumps are the most efficient and have a longer life, therefore they are the most commonly employed pumps found on a quality power washer today.

There are duplex and triplex plunger pumps. Plungers are typically made of ceramic, a very hard material with excellent wear resistant characteristics. The triplex pump has become the most popular due to the smoother flow it creates.

These pumps are incredibly robust and virtually trouble free when properly maintained. Most people suspect the pump first when experiencing a problem but amazingly 90% of problems can be traced to causes other than the pump.

HIGH PRESSURE HOSE

A high pressure hose is composed of an inner tube in which the water flows. This is wrapped in either a single or a double braid of wire mesh. This is in turn surrounded by a rubber outer cover. The cheaper hoses are covered in a thermoplastic material the better hoses have rubber covers. Most hoses are manufactured with burst ratings 4X their rated working pressure. When matching hoses to machines try to use a hose rated slightly higher than the psi rating of your machine. It will last longer. Typical psi ratings are 3000psi, 4000 psi, 4500 psi, 5000psi and 6,000 psi. 3,000 and 4,000 psi hoses are generally single braid while 5,000 psi and above are virtually always double braided (2-wire).

PRESSURE WASHER DESIGN

A good pressure washer hose is the same design principle as a hydraulic hose. The basic construction is as follows:

1. Inner Core – This is the inner core in which the water actually flows.
2. Wire Wrap – This is the wire wrapper that surrounds the inner core and protects it from damage. This wrap is in a braided configuration which allows the hose to bend freely while having ample protection. Most Hoses under 4500 psi ratings have single wire wraps and are referred to as “single wire or R-1″ hoses. Hoses designed for psi ratings of 5,000 or above and hoses designed for hot water use have two wire braids and are referred to as “2-wire or R-2″ hoses.
3. Outer Cover – The best covers are rubber, thermoplastic covered hoses are widely used on pressure washers that are designed to be sold at a cheap price. If quality is important to you I would be sceptical of machines that are sold with a thermoplastic hose as standard.

Exception: The most notable exception is in the case of sewer jetting. In this case the pressure washer is designed to unblock and clean sewer lines. For this application 1/4″ and 1/8″ thermoplastic hoses are an advantage due to their ability to make extreme bends within pipes.

The standard size for pressure washer hoses is 3/8″OD (outside diameter). This is because the vast majority of pressure washers are rated between 3-5 gallons per minute flow rates. If your system exceeds a flow rate of 5gpm or if you are planning on using more than 100′ of hose continuously then consider 1/2″OD hose. Many lesser pressure washers of dubious quality market pressure washers with 1/4″ thermoplastic covered hoses in 25′ lengths. For me this has always been a tipoff to investigate quality issues further prior to any purchase. Standard quality hoses come in 50 ft lengths.

TIP: If you are planning to use 100 ft or more hose continuously don’t buy a 100 ft hose, buy two or more 50-foot hoses and link them together as that way if a hose goes bad or wears out you can keep working and you don’t lose an extremely expensive hose.

A black or red rubber hose can leave marks on surfaces, this can be a concern when pressure washing roof tiles or when doing flat work on concrete. In these cases use blue or gray covers these do not leave marks or scuffs and are referred to as “non-marking hose”.

Yellow coverings are typically made so that the hose is more resistant to the effects of oil, grease, and animal fats these are often used in rendering plants and other industrial applications. If you are working at heights, remember that all the weight of the pressure washer hoses when filled with water can be pulling on the hose fitting.

The best manufacturers sell pressure washer hoses that are skived before coupling. Skiving means the outside rubber cover is partially removed to allow the metal fitting to be crimped to the wire braiding of the hose. This process provides a solid metal to metal solution with good strength.

TRIGGER GUNS

Considering there are numerous styles of pressure washers, the appropriate trigger gun should complement the whole pressure washer to maximize it for best use and there are also different styles available to pressure washers today.

• Pistol Style Guns
• Straight-Through Guns
• Front Entry Guns
• Rear Entry Guns
• Dump/ Weep guns
• Open Guns

Trigger guns that stop the water flow are the most commonly used guns in power washer systems equipped with unloader valves. Front entry guns are common on the lesser priced units and rear entry guns are far and away the most popular. Rear entry guns do a better job of keeping the hose out of the operators’ way and are better balanced.

These guns control the water flow via a spring, ball and seat which are actuated by the trigger. When the trigger is released the ball is pressed against the seat by the spring and water, aided by a check valve in the outlet of the unloader. Water is “trapped” in the hose under pressure and the pump enters bypass mode.

With this setup you will experience some “kickback” when you squeeze the trigger so be careful when using ladders and other types of access equipment. Dump Guns and open guns are operated without unloader valves because they don’t stop water flow.

The standard pressure washer trigger gun which almost every manufacturer supplies, either a front or rear style pistol gun which stops the flow of water and necessitates the need for an unloader valve. These guns have long been considered to be the industry the standard.

THE UNLOADER VALVE

This is the main “safety” in your power washer system. The most commonly used is the “pressure actuated” type valve. When the pressure gun trigger is released the valve senses the pressure build up and like a “traffic cop” it diverts the water flow from the pump outlet back into the inlet side of the pump this is called “bypass mode.” Without this critical component this closed-gun situation would build pressure to the point where it would stall the power source, rupture the gun, hose or even the pump itself.

HIGH PRESSURE NOZZLES

These simple seemingly insignificant components are what make the whole high pressure system work. Pressure washer nozzles contain a small orifice which is sized to create the desired pressure at a specific flow. This orifice is a restriction in the water flow. When the flow from the pump is forced through this restriction pressure is created. It is only now that you have a pressure washing system. Pressure washer nozzles with an orifice that is most closely sized to the specs of your pump will give you the optimum performance. The high pressure nozzle is a much more important component to the power washer than most realize. This creates the restriction that allows the water flow to become “pressurized” and delivered with such force. A worn nozzle will reduce pressure noticeably. A mismatched orifice can have the same effect. A nozzle with little to no wear and one with an orifice properly sized to your pumps’ output will get the most performance from your machine.

This is the last post is from a series of six on

Everything You Ever Wanted To Know About Pressure Washing.

Part One : What Is A Pressure Washer

Part Two : How Does The High Pressure Washing Work

Part Three : What Can A Pressure Washer Used For?

Part Four : How To Use A Pressure Washer

Part Five : What Are The Different Types Of Pressure Washer

Part Six : Parts Of A Pressure Washer

The easiest way to learn how to use a power washer is to first understand how the power washing systems work. There are four basic elements of the power-washing process regardless of what machine or method you use.

The four elements and power washer tips are: pressure, water flow rate, cleaning solution and heat. If we take out just one of these four elements, the cleaning characteristics will change. For example, if you can only afford a cold water pressure washer instead of hot water washer, you will have to compensate for that loss. In other words, pressure washer basics tell you that you will have to add more chemicals, apply higher pressure and use more water to achieve better power wash results. Therefore, you will always have to make adjustments combining these four elements in order to achieve the ideal cleaning atmosphere for your particular job. Nevertheless, when learning how power washing systems work and how to power wash, keep in mind that detergents emulsify the dirt better and faster as the temperature increases. This is especially true when cleaning oil and grease from a concrete surface. That’s why hot water power washing systems are perfect for such jobs.

This is the fourth post is from a series of six on

Everything You Ever Wanted To Know About Pressure Washing.

Part One : What Is A Pressure Washer

Part Two : How Does The High Pressure Washing Work

Part Three : What Can A Pressure Washer Used For?

Part Four : How To Use A Pressure Washer

Part Five : What Are The Different Types Of Pressure Washer

Part Six : Parts Of A Pressure Washer ]]> http://www.ryobipressurewasher.com/how-to-use-a-pressure-washer/feed/ 11 http://www.ryobipressurewasher.com/what-can-a-pressure-washer-be-used-for/ http://www.ryobipressurewasher.com/what-can-a-pressure-washer-be-used-for/#comments Tue, 16 Mar 2010 12:18:18 +0000 jerome_bringas http://www.ryobipressurewasher.com/?p=79 Continue reading →]]>

• • A pressure washer cleaning oil-logged asphalt
  • Graffiti removal
  • Car Wash
  • House Washing
  • Industrial Washing

USES OF PRESSURE WASHER

This is the third post is from a series of six on

Part One : What Is A Pressure Washer

Part Two : How Does The High Pressure Washing Work

Part Three : What Can A Pressure Washer Used For?

Part Four : How To Use A Pressure Washer

Part Five : What Are The Different Types Of Pressure Washer

Part Six : Parts Of A Pressure Washer ]]> http://www.ryobipressurewasher.com/what-can-a-pressure-washer-be-used-for/feed/ 0 http://www.ryobipressurewasher.com/how-does-high-pressure-washing-work-2/ http://www.ryobipressurewasher.com/how-does-high-pressure-washing-work-2/#comments Mon, 15 Mar 2010 11:46:01 +0000 jerome_bringas http://www.ryobipressurewasher.com/?p=73 Continue reading →]]>  Pressure washing is in fact the process of breaking the bond between the dirt and the surface being cleaned. As we mentioned earlier, for the best results you will combine four essential elements. However, shortfalls do exist. Here is another example of how pressure washers work: let’s say you notice you have a little detergent left and you decide to decrease the amount injected through pressure washer. A cleaning solution decrease in this case will have a less effect on the debris being cleaned. Because of that, now you must work with other elements to make up for that loss. You have to increase the pressure, water temperature and the water volume. Even though, you are less likely to reach the same level of efficiency (by decreasing the amount of detergent), you will somewhat neutralize that loss.

This is the first post is from a series of six on

Everything You Ever Wanted To Know About Pressure Washing.

Part One : What Is A Pressure Washer

Part Two : How Does The High Pressure Washing Work

Part Three : What Can A Pressure Washer Used For?

Part Four : How To Use A Pressure Washer

Part Five : What Are The Different Types Of Pressure Washer

Part Six : Parts Of A Pressure Washer

The most basic pressure washer consists of:

•     A motor which directly drives a water pump
•     High-pressure hose
•     Trigger gun-style switch
•     Nozzle Tips (Depends on the intended applications)

Just as a garden hose nozzle is used to increase the out flowing dynamic pressure of the liquid, a pressure washer adds its own power to force high-dynamic pressure. Note that the pump does not draw more water from the pipe to which the washer is connected than that source can provide; therefore, the water supply must be adequate for a given machine to be connected to it: its flow must be equal or superior to that of the washer, so that the pump is never starved (which can damage it).

Several different types of nozzles are available, each useful for a particular application. Some nozzles cause the water jet to be ejected in a triangular plane, while others emit a pencil-thin jet of water, which spirals around rapidly. Most nozzles attach directly to the trigger gun.

Some pressure washers, in combination with a particular nozzle, allow detergent to be introduced into the water stream, assisting in the cleaning process. Two types of chemical injectors are available: a low-pressure injector and a high-pressure injector.

Pressure washers are dangerous tools and should be operated with due regard to safety instructions. The water pressure near the nozzle is powerful enough to strip flesh from bone. Objects in the water supply can be ejected from the nozzle at great velocities. The cleaning process can propel objects from the surface being cleaned, also at great velocities. Pressure washers have a tendency to break up asphalt if aimed directly at it, due to high pressure water entering cracks and voids in the surface.

Most readily available consumer units (commonly found online or at hardware stores) are electric or gas-powered. The electric ones plug into a normal outlet and use/produce cold water, and typically deliver pressure up to about 2000psi. Gas-powered units can often deliver twice that pressure, though due to the hazardous nature of the gasoline exhaust they are unsuitable for enclosed and/or indoor areas. Some models can generate hot water, which can be ideal for loosening and removing oil and grease.

This is the first post is from a series of six on

Everything You Ever Wanted To Know About Pressure Washing.

Part One : What Is A Pressure Washer

Part Two : How Does The High Pressure Washing Work

Part Three : What Can A Pressure Washer Used For?

Part Four : How To Use A Pressure Washer

Part Five : What Are The Different Types Of Pressure Washer

Part Six : Parts Of A Pressure Washer