Pressure Washers: The Ultimate Guide

Life has a funny way of leaving its mark on your garden. Over time, mud, mould, and mildew will grow on the surfaces of your patio, decking, and paving.

Luckily, pressure washing is an easy, efficient solution to bringing the shine back to your garden. In this guide, we’ll tell you everything you need to know about pressure washers. Keep reading to learn more…

What is a pressure washer?

A pressure washer, sometimes called a power washer, is a powerful cleaning device that generates a high-pressure stream of water capable of removing dirt, mould, and other contaminants from surfaces.

They are operated by a motor or engine, which drives a pump tasked with pressurising water from a connected water source. The pressurised water is pushed down a hose, along the lance, and out of a nozzle, creating a powerful jet.

The nozzle can be adjusted to vary the pressure of the water, or the spray pattern, which allows for a greater control depending on the cleaning task.

The pressurised water hits the surface with high kinetic energy, loosening and forcing the attached grime free from the surface.

Who invented the pressure washer?

The history of the pressure washer actually goes all the way back to the famous Prohibition era of America. During this time, traders operated in an underworld alcohol business to supply consumers without being caught.

The concept came from one such trader. Frank W. Ofeldt II discovered the concept accidentally while trying to think of a way to design his portable whiskey. 

Ofeldt inadvertently developed the cleaning device when he noticed that the steam from his whiskey stills was capable of removing the grease stains from the engineering process. He would later go on to invent what was essentially a steam-powered cleaner.

However, the man widely recognised as the inventor of the modern pressure washer is German inventor, Alfred Kärcher. In the 1950s, Kärcher was responsible for inventing the world’s first hot water, high-pressure washer, the DS30 high pressure washer.

Is a pressure washer the same as a pressure cleaner?

Not quite. The biggest difference between a pressure washer and a pressure cleaner is that pressure cleaners are designed to be portable, and do not need to be attached to a mains water supply to function.

While most come with an attachment that makes them adaptable with a mains tap, pressure cleaners usually draw water via a suction hose. This makes them more lightweight, but will take longer to pressure clean an area when compared to a pressure washer.

Features of a pressure washer

Before we get into the specific factors of a pressure washer, it is good to understand the various terms and features that are used when perusing different types of pressure washers. Here are some of the most common features:

Hose

This is the length of the hose that connects the nozzle to the main body of the pressure washer. Lengths usually vary from 2 to 15 metres, so the length you choose will depend on the task at hand.

Larger lengths are advisable for manoeuvring around cars, or cleaning long stretches of fence, whereas shorter lengths will be suitable for garden furniture, or small patios.

Of course, cordless pressure washers have no hose at all, so if the prospect of a hose does not suit your fancy, keep that in mind.

Lance

The lance is the part of the pressure washer between the nozzle and the trigger. It can provide additional control over the flow of water without increasing water usage.

A long lance can be of great use for getting into those difficult to reach areas, such as low places where bending could injure your back.

Short lances will improve agility when performing a light wash, as they have a lighter weight than their longer counterparts.

Another great addition is an angled lance. This attachment can be great for cleaning out gutters that are out of reach, as the angled end can give you the dexterity required to face the stream directly into the gutter.

Portability and storage

Storage and portability are important aspects to consider in a pressure washer. The bodies of most pressure washers have side-mounted compartments to allow for practical storage of hoses, nozzles and cables, which makes it much more convenient when it comes to tidying it away.

The larger the job, the more likely you are to need to move around with your pressure washer. Moving a pressure washer around can be difficult, so look for one with a good handle and set of wheels.

Plastic wheels will be fine on flat, smooth surfaces, but will struggle on bumpy, uneven surfaces. In these instances, consider a pressure washer with rubber wheels, which are more suited to difficult terrain.

Don’t forget about the handle, either. A low handle is fine when the pressure washer is light enough to carry, but will cause backache if you attempt to wheel it around often. A long handle will take the ease out of pushing and pulling the pressure washer, but will make it harder to carry.

Nozzles and attachments

One of the biggest considerations to make when selecting a pressure washer is the type of nozzle or attachment used. Each is designed to cater to a specific task, so getting it right is important.

Auto start attachments are a common mainstay of most modern pressure washers. It is a trigger on the handheld part of the device that allows for controlled bursts of water. This is a convenient feature as it cuts down on water waste over models that must be activated on the body of the pressure washer.

Surface cleaner attachments use a spinning bar to distribute high-pressure water over a large surface area. It is great for cleaning large sections of concrete, such as a driveway.

Rotary nozzles produce a spinning zero-degree water stream. This is very useful for removing difficult stains, and a build-up of grime.

Pressure washing brooms divide a single jet of water into two or three to increase the power, and clean a larger area more efficiently.

Soap reservoirs are great for adding a cleaning solution to your jet of water. They attach to the pressure washer, and are injected into the stream. Just make sure that you pair it with the correct type of nozzle.

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Understanding power, pressure, and flow rate

There are three different ways power and pressure factors in to the pressure settings of a pressure washer, power, water pressure, and water flow rate:

Power

The pump plays a big role in a pressure washer. It is used to create and increase the pressure of water flowing through the hose. Pressure washers come with three types of powered pump: petrol, electricity, and cordless.

Petrol powered pressure washers usually provide a higher PSI (pounds per square inch) and GPM (gallons per minute) than their electric counterparts.

This additional power allows them to clean faster and more efficiently, and as they are powered by a petrol engine, they have no need for a cord, allowing them to be used much more freely than an electric model.

However, the petrol engine is undoubtedly louder than an electric pressure washer, and produce carbon dioxide emissions, meaning that they should never be used in covered areas, or indoors. They also require regular maintenance to ensure the engine is running efficiently.

Electric pressure washers in this regard are more convenient, as they only require an electrical outlet. Coupled with an extension cable, an electric pressure washer can be nearly as mobile as a petrol engine pressure washer.

However, they lack the same level of power, which will slow down the process. This will be especially notable when cleaning large, dirty areas.

Last, we have cordless pressure washers. Similar in design to electric pressure washers, they require a power outlet to charge a battery before use. Then they can be used freely without worrying about a cord.

They are ideal for domestic use as they are lightweight and portable, but will require a water source nearby to constantly top up their water supply.

Water pressure

The water pressure is measured either in pounds per square inch (PSI), or bars. Pressure washers can usually range from 90 bar, up to 280 bar.

Choosing the right pressure and flow rate is important to avoid damaging the surface, while still effectively removing the dirt.

Think about what it is you are cleaning, and how often you intend to clean it. Frequent cleaning can wear down the resilience of certain surfaces, and may therefore require a lighter pressure.

In general, a light pressure setting should be used for delicate surfaces, windows and screens, or garden equipment or furniture. This is to prevent the likelihood of damage occurring. It is advised for use on bicycles or small cars, where there is a risk of stripping paint or causing abrasion.

A medium pressure setting is suitable for cleaning driveways, pathways and patio. It will also be effective against dirt and mildew that clings to fences and decking. Larger vehicles, trucks, or boats should also be cleaned on this setting.

Lastly, there is the heavy pressure setting. This is ideal for tackling tough dirt, or harder surfaces, such as concrete. It can be used to strip paint, or remove heavy build-up and graffiti, and has widespread use in commercial cleaning, or construction sites.

Water flow rate

Last, we have the water flow rate. While both water flow rate and water pressure play a role in the performance of a pressure washer, they serve different purposes.

Whereas water pressure determines the cleaning force, water flow rate determines how much water is used during the cleaning process.

Water flow rate is measured in gallons per minute (GPM), or litres per hour (L/H), and indicates the volume of water that flows through the pressure washer. 

It reflects the power and efficiency of the pressure washer, as higher flow rates can cover larger areas and remove dirt faster.

Conversely, washing a car would require a lower GPM to prevent damage to the paintwork.

What motor type should you use?

There are three main motor types that typically come installed on pressure washers. While this isn’t something you need to worry too much about, having a better understanding of how each motor works can make it easier to make an informed decision.

Brush motor

First up we have the brush motor. These motors contain brushes which are constantly in contact with the rotating part of the motor, also known as the commutator, creating a circuit to transfer electrical power.

Brush motors are generally cheaper to manufacture, making the end product more affordable. Their simplistic design makes them easy to repair, and they are capable of providing high torque at low speeds, which can be beneficial.

However, the friction caused by the constant motion of the brush on the commutator can make them wear out much faster than other motors. They are also noisier, and less efficient than other motors.

Universal motor

A universal motor is a lightweight, compact motor known for its simplicity and high speed. Its lightweight makes it suitable for portable pressure washers, as it boasts an impressive power-to-weight ratio.

Although the design of a universal motor means that they generate a lot of heat, so will require more breaks, or additional cooling solutions to prevent overheating. They are also fairly loud, and have a shorter lifespan due to the high speeds at which they operate.

Induction motor

The induction motor is a popular choice for industrial-grade pressure washers. Sometimes known as asynchronous motors, they rely on electromagnetic induction to produce torque.

The design of the induction motor allows it to provide consistent, steady power without the risk of overheating. They also run much quieter than brush and universal motors, making them a suitable choice for residential areas. With fewer moving parts that can wear out, induction motors are built to last, and are more energy-efficient.

Another key difference between the motors is that brush and universal motors are air-cooled, whereas induction motors are water cooled.

However, these benefits come at a cost. Induction motors are more expensive to produce, and their complex design can make maintenance more challenging. They are also heavier and bulkier, making them less ideal for portable pressure washers, or prolonged use.

What is the best pressure washer?

That question will depend on the task at hand. The pressure applied to a surface will determine how effectively it will be in removing dirt and grime. Take some time to consider your needs before you select a pressure washer.

Best pressure washer for car cleaning

Cleaning cars has become a popular pastime for many a car owner. But knowing what pressure washer to use on a car depends on the use of the vehicle.

For standard cars driven for everyday use, a light or medium duty pressure washer should suffice. Look for a pressure washer that can achieve up to 130 bar to clean light mud and grime away.

If you like to stray off-road in your vehicle, you will need something a bit more heavy duty. To remove tough mud, a pressure washer capable of over 130 bar should be up to the task.

Also keep in mind the water flow rate. A high flow rate will rinse off your car faster, while a low flow rate will take longer.

You should also find a pressure washer will a longer hose to take the hassle out of manoeuvring around your car.

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Best pressure washer for decking and fence cleaning

The first thing to consider when selecting a pressure washer to use on wood decking and fences, is the type of wood being cleaned.

Softwood, such as pine, cedar, fir, and redwood, should be cleaning with a light duty pressure washer. Anything with up to 100 bar should do the trick, removing dirt, algae, and mildew, without damaging the wood.

For hardwoods such as oak, birch, and larch, a pressure washer with between 100-130 bar is recommended. Anything stronger than that can still cause damage to the wood, while anything less may struggle to remove that ingrained algae.

A portable pressure washer, or one with a long hose, are recommended for use on fences or decking.

Best pressure washer for block paving cleaning

Over time, block paving accumulates tough dirt, moss, and algae in its crevices, which require a certain amount of pressure to remove.

For domestic use, block paving should be cleaned with a pressure washer with 100-130 bar rate, which should clean out those tricky nooks and crannies easily enough. 

For professional, or more frequent use, you may want to consider a heavy-duty pressure washer. Over 130-150 bar with a high flow rate of at least 400 l/h will make quick work of larger, dirtier block paving.

It would also be wise to consider a special patio cleaning nozzle attachment, which is less likely to blast away the sand between the joints.

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Best pressure washer for patio cleaning

When cleaning a patio, a medium-to-heavy-duty pressure washer is recommended. The key will depend on just how grand the task at hand is.

A pressure washer with between 100 and 130 bar, and a medium flow rate should make quick work of a light layer of dirt or algae. 

However, if you need to wipe away years of tough grime, you want to go big. Anything over 130 bar, with a heavy flow rate, will give you the best chance of bringing back a clean patio.

Also consider a long lance on your pressure washer. Prolonged washing hunched over a short-lance pressure washer will put strain on your back.

Best pressure washer for concrete cleaning

Last, but not least, we come to concrete cleaning. Similar to patio cleaning, the pressure level will depend on how dirty your surface is.

Concrete is designed to be very resilient, so err on the side of power to get the job done. Any pressure washer with a pressure rating between 120-150 bar is a good choice for uprooting that tough grime that clings to concrete.

Again, consider a long-lance pressure washer, and an attachment that will diffuse the spray of water over a larger area.

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Still unsure which pressure washer to pick? The table below should help you to understand which pressure washer is right for you:

Duty

Light

Medium

Heavy

Flow rate

Up to 350 l/h

350 - 410 l/h

420 + l/h

Bar

Up to 100 bar

110 - 135 bar

140 + bar 

Cars

Decking

Fences


Garden furniture



Patios


Block paving



Concrete paving


Find the best pressure washers at Hughie Willett Machinery

At Hughie Willett Machinery, we stock a large range of high-power pressure washers from top brands including Stihl and Husqvarna. We offer the full range of pressure washer accessories from both manufacturers.

Keep pavements and patios satisfyingly clean with our range of portable pressure washers. From different sizes and designs, handheld to wheeled models, we can help you find the best power washer to suit your needs.

Not only that, but our friendly and experienced team are available to provide you with all the advice and guidance you may need to make an informed decision.

Have more questions about your hand tool maintenance? Contact us online, or call 0121 308 1262 to speak to a member of our team who will be happy to answer any queries.

Find pressure washers at Hughie Willett Machinery

For more news, machinery and equipment buying guides, advice, and information, explore the Hughie Willett blog

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