Karcher K5 pressure washer review: tackle outdoor cleaning on ‘any type of surface with confidence’

There are times when a scrub down with a bucket and brush just ain't enough. Indeed, even when you add a hose and a spray nozzle into the equation, it just doesn't cut the mustard (or grime). Outdoor and garden cleaning can present you with some of the toughest dirt to tackle (Mother Nature knows her stuff), and this is where pressure washers really come into their own. To bring that 'wow factor' back to your garden and patio, I've reviewed the Karcher K5 pressure washer - a Karcher high-to-mid-range pressure washer, made for "the discerning".

Having produced its first modern pressure washer in 1950, Karcher is today one of the leading players in the UK marketplace. With its yellow and black uniform synonymous with pressure washing, its range includes everything from battery-powered models, which are handy for camping trips or for washing your bike or dog after a particularly muddy expedition, up to powerful professional industrial machines. Ranging from K2 to K7, the K5 isn't necessarily for beginners; it's a robust tool for those looking to oust stubborn dirt over a large area.

I should begin by saying that I have enjoyed the services of a Karcher K4 for a few years now, so I was looking forward to seeing how its more powerful brother, the Karcher K5, fared. The particular model on test was the K5 Power Control Car & Home.

Karcher K5 pressure washer overview

Testing the Karcher K5 pressure washer

What's included?

The Karcher K5 Power Control Car & Home is an all-embracing collection of pressure washer accessories to help you get the best from the K5 around the home and garden and for keeping your car clean, too. My previous K4 was a basic model with no extras to distract me; with all the additional bits of kit on this K5, there were plenty of toys to play with. As standard, it comes with:

A power control spray gun: This is the pressure washer equivalent of your gaming controller, albeit a little more basic
Two lances: The first is the Vario Power Spray lance, which can be adjusted from a soft spray to a powerful jet. The second is the Dirt Blaster, which is ideal for tackling the toughest stains but needs to be used with care.
A detergent gun foam jet: You can quickly and evenly give your car (or whatever you are working on) a covering of foam detergent.
A rotating wash brush: Another handy helper for tackling tougher stains - also good on car wheels
A T5 patio cleaner: Ideal for tackling patio, decking and driveways
You also get a handy chamois leather to dry off any surfaces for a streak-free finish.

I also received the Eco Booster 145 attachment, which Karcher claims will deliver a 50 per cent increase in cleaning performance over the standard flat jet, meaning you use less water and save time. It's kind of difficult to ascertain just how efficient these attachments are without setting up your own laboratory, but I certainly didn't see any reduction in the jet performance. It also did cover a larger area as I was cleaning, meaning I spent less time on the job. So in a non-scientific way, I would have to say that it does appear to save time, so it must save water and as you can cover a larger area, it saves you energy as well.

Getting to grips with the Karcher K5

You can't just take the K5 out of the box and use it; there is a bit of assembly required. For this, it is worth reading through the instruction booklet first. Initially, there are pictorial instructions, which can be a little difficult to decipher, but there are written instructions a few pages further on. Having said that, I had everything fitted and ready to go in about 30 minutes.

Getting the K5 ready to go is pretty straightforward, with all the water connectors being the quick click-to-fit type, so there's no need for any tools. The main pressure hose is 10 meters long, which means you can move around quite freely without having to pull the pressure washer after you. And sometimes, the simplest of design features can make life so much easier.

In the case of the K5, it's a hole. Yup, a simple opening through the body of the washer allows the pressure hose to be fed through from the rear, where the pressure outlet is, to the front where the controls are. It also helps separate the water hoses from the electrical mains connection. I did find it difficult to connect the high-pressure hose to the spray gun, but once it was secured, it was a good, tight fit and easy to remove when clean-up time came.

The Karcher K5 weighs just under 15kg, so it's not the lightest machine, but it does come with wheels and a telescopic transportation handle.

Using the Karcher K5

We have a section of monoblock paving where we regularly park our car—the difference in shading in the photograph below might give you a clue as to where the car sits. The whole area looked a bit sorry, so it was the ideal candidate for a K5 makeover. The ideal accessory for this is the T5 Surface Cleaner. Under the circular yellow housing, this has a twin-jet rotating arm, which allows you to vastly speed up the cleaning process and gives you a much more even and constant clean. It's adjustable so that it can be used for hard surfaces like stone and concrete as well as more delicate materials such as wood. The added bonus is that the hood helps to protect you from being sprayed by dirty water.

Cleaning flat surfaces

The T5 connects to the power control spray gun using the quick-click connectors and is ready to go in no time. Like anything, it took a few moments to find my groove, but once I relaxed into it, I found it easy to work with. The powerful water jets from the rotating nozzles create a kind of hovercraft effect, which makes the T5 really easy to move around. I also used it on our pathway, which is made of individual paving stones which, over the years, have settled at slightly different heights, and I sometimes found the T5 could get caught on the ridges. It is quite an efficient way of getting patios and decking areas cleaned up quickly with the minimum of fuss and getting good results, too.

If you are being fussy, you may find that you have to go over certain areas, especially in corners, where the T5 might not have fully reached with one of the lances. I used the Dirt Blaster lance, which tackled the corners of the monoblock and the paving with no problems whatsoever.

Car cleaning

Rather than having to sit in the queue at the local car wash, you can use the lances supplied with the K5 to get the job done yourself. I used the vario lance and the detergent gun foam jet. The gun foam jet has an adjustable nozzle so that you can control how much foam you use, depending on how dirty your car or the surface you're cleaning is. I found attaching it a bit awkward, as the nozzle turns as you are trying to rotate the assembly onto the power gun. You have to get the positioning correct, or the gun foam jet will sit at an odd angle.

The foam is delivered quickly and evenly and covers the car in a nice white coating which will get to work dissolving the grit, grime and grease. Perhaps I'm exaggerating there as the testing was done in the 'summer' months when the biggest enemies are bugs, road tar and that summer dust that seems to appear out of nowhere.

On the K5, there is a detergent bottle connection. It allows you to attach specially shaped bottles of Karcher detergent, which will feed the liquid directly through the machine to the spray nozzle. The amount of detergent used can be adjusted as necessary by using the vario-lance nozzle. So far, this is the nozzle I have found myself using the most, as it can be adjusted to provide a gentler pressure for more delicate surfaces and increased to tackle tougher jobs.

The combined spray gun and nozzle are fairly light and easy to work with, and the 10-metre-long hose gives you a huge amount of freedom to walk around as you work without constantly moving and repositioning the power washer.

As expected, the K5 didn't have any problem battling the dirt. There is no doubt that this machine packs a fair old punch. You can feel the kickback when you pull the trigger, but that power helps to shift the dirt effectively and efficiently. Most domestic pressure washers will operate at around 120 Bar—the K5 will deliver an impressive 145 Bar. The Vario lance is ideal for car washing as you can use the full power to blast the dirt off and then reduce it to a gentler spray for the final rinse-off.

Are there any negatives?

No, not really. No negatives as such, perhaps just a couple of niggles.

When I was first connecting the high-pressure hose to the lance, it was difficult to get in place, although I suspect this was just due to newness. Subsequently, I haven't had any issues.

Also, and there may be a degree of operator stupidity here, I found the procedure of attaching the vario lance and detergent holder to the spray gun a bit difficult. You need to twist the nozzle into place. Unfortunately, my natural grip tended to hold the moving adjustable part of the nozzle, making it a bit awkward.

I have to say, I'm not terribly impressed with the telescopic transportation handle. As a unit, the Karcher K5 is a tightly built, solid, sturdy bit of kit. Unfortunately, the handle seems a bit loose and wobbly. It does the job and is perhaps not an important factor in the K5's cleaning performance, but it just took a little bit of the shine off for me.

Final verdict: Is the Karcher K5 worth it?

I liked working with the Karcher K5. It is a great home workhorse, probably as powerful as you would need for just about any domestic situation, with enough accessories to give you the flexibility to tackle cleaning jobs on just about any type of surface with confidence. The development of the Eco Booster 145 attachment is a great addition to the Karcher stable as it offers savings on water and energy with no noticeable reduction in effective performance.

4.5/5

How this product was tested

The Kärcher K5 Power Control was extensively tested. First, it was used to give my car a couple of weekly cleans and an initial clean where it hadn't been washed for a few weeks. Here, we tested the car cleaning power, durability, and manoeuvrability. It’s since been used to test the T5 surface cleaner on monoblock paving, the vario lances on a number of different materials, including paving, stone and wood, and for general garden and home power washing.

Other options to consider

What to read next:

Best pressure washer deals for outdoor cleaning jobs this summer

Best Kärcher pressure washers for a powerful yard clean

Clean up with the best Kärcher pressure washer deals

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Alex Boyd is a Commercial Content Writer for CAR, Parkers and Modern Gardens, specialising in power tools and pressure washers. He’s still a big fan of the cars from the ’70s and ’80s, is a lapsed member of the IAM and enjoys driving all types of vehicles, from his first Mark 2 Ford Escort to Tri-Axle Double Decker buses. In his spare time, he enjoys DIY, travel, and music.