Karcher K4 Review – K4 Full Control & K4 Compact Models Compared

Last updated on November 25th, 2023

KARCHER K4 REVIEW 

The Karcher K4 Pressure Washer is a step up from the smaller, entry-level K2 pressure washer and comes with improvements and new features making it a more serious model and a great option for those who looking for an affordable pressure washer for tackling larger paths, patios and driveways and of course cars and vans.

What you will get from this review?

What you may not know is that there are two different Karcher K4 models. The K4 Full Control Pressure Washer is packed with the latest features (which we will discuss in more detail) and the Karcher K4 Compact Pressure Washer, which, as the name suggests, is more compact, has the same pressure rating, hose length but has less of the fancy features such as a standard spray gun instead of the fancy LED stray gun and a detergent suction tube instead of the new ‘plug n clean’ detergent system the K4 Full Control Pressure Washer has.

Below we will start by reviewing the more expensive Full Control Pressure Washer, the pros & cons, what features it has and all that good stuff and then we will review the Karcher K4 Compact model.

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  Kärcher K4 Full Control Home Pressure Washer Review

The Karcher Full Control Home Pressure Washer is one of the best selling Karcher pressure washers, and it’s no surprise. It combines a compact design and a wide range of innovative features, making it a top pressure that’s worth every penny. Let’s look into the facts that make it such an astounding pressure washer.

The Karcher K4 pressure washer combines a new innovative stylish design with some excellent storage options to ensure everything is kept to hand. It has some great features that make it unique from other brands such as the very convenient ‘plug n clean’ detergent system and LED gun so you know what pressure setting you have it on instantly. If you are looking for something with a little more power than the entry-level models then the K4 is a great alternative and the 3-year warranty only adds to the value. We found the hose connections do not swivel, this means the hose does not turn so it can seem stiff and sometimes tends to try and turn when in use. Not a deal-breaker but it is something we felt was worth mentioning.

Pros

• A powerful 1800w water cooled motor which prolongs the life of the washer.
• Easy assembly – the process takes just a couple of minutes due to easy guides on the handle and lances and quick connect hose.
• Has an ergonomic design, fitted wheels and adjustable handle that makes it easy to manoeuvre from one place to another.
• Provides onboard storage for accessories which ensures it takes up little space in the garage or shed.
• Comes with a relatively long 6 meter hose for effective reach in wider areas.
• Has an LED indicator on the spray gun to show the pressure you select to work with.
• Comes with two lances, one vario lance with adjustable pressure and one dirtbuster lance.
• Plug n Clean detergent system makes using detergent hassle free. (No suction tube to deal with)
• 3 Year warranty for full peace of mind

Cons

• The quick click connectors for the hose do not swivel, this means that sometimes the hose can tend to turn left or right so you have to hold it firmly. 

Specifications and Features

• Pressure (bar/MPa) – 20 up to 130 / 2 up to 13
• Maximum flow rate – 420l/hr
• Maximum inlet temperature – 40 degrees C
• Current type – 230V / 50Hz
• Connection load – 1800 watts
• Area performance – 30 sq. m/hr
• Weight (without accessories) – 11.4kg
• High pressure hose length – 6m
• Dimensions – 39.7 x 30.5 x 58.4 cm

1800w water cooled motor

The Karcher K4 Full Control Home Pressure Washer is designed to deal with a fair amount of dirt on the patio, decking, cars, walls and other outdoor structures. It is fitted with a 240v water-cooled motor that delivers a maximum of 1800 watts of power. Keeping in mind that continuous running of a motor leads to great heat production, this water-cooled motor is sure to run long owing to continuous heat management and is simply a much better motor than air-cooled motors like that found on the Karcher K2.

130 bar of power & 4 pressure setting all controlled by the lance

This machine benefits from 4 different pressure water pressure ratings. The lowest pressure is ideal for applying detergent whilst the three other settings deliver high pressure, however, they vary significantly to suit different tasks. The maximum pressure is 130 bar and at this setting, you can wash an equivalent area of 30 square meters in an hour.

Another impressive feature to note is the maximum flow rate – 420l/hr – which is just enough for medium cleaning tasks. If you need more than this, maybe something to deal with stubborn dirt, you can upgrade to the Karcher K5 models which have slightly better performance or even the Karcher K7 Premium if you are looking for something suitable for the most demanding cleaning jobs and larger areas.

New LED trigger gun to see current pressure setting

Featuring a full control trigger, it is easy to control the hose’s activity and inactivity. In addition, the trigger has an LED indicator that always shows the power you select for particular tasks.

The Karcher K4 also comes with full control lances. One of them is the vario lance and this allows you to vary the water pressure via a simple swift twist on the barrel. Whichever way you alter the pressure, you will see the result on the display. The other lance is the dirtblaster, this forms a powerful circulating jet to remove stains from surfaces or remove tough dirt from weather-worn surfaces. For increased convenience, there’s onboard storage for the lances plus the electrical cable.

When it comes to using the detergent, this model uses the plug n clean system which we do think is a big improvement on the suction tube alternative. Simply plug the bottle of detergent into the pressure washer and it can now be used with the detergent setting on the LED trigger gun. Keep in mind that this unit comes without the detergent, however, there are provisions for purchasing it with some useful accessories including the detergent at a slightly higher price.

In that regard, the set we have reviewed doesn’t come with a free detergent but you can either upgrade to get a package with detergent or buy it separately. But once you have it, the Karcher’s Plug and Clean System makes it easy to use the detergent right away. A built-in water filter also prevents large particles from entering and probably damaging the pump.

Speaking of the build, the Karcher K4 Full Control boasts a portable and ergonomic design. The machine’s portability is enhanced by its telescopic handle and large wheels. If you need to move the pressure to the other side of the garden, simply drag or push it along without having to lift it.

After you are done with your duties, you can pack the unit nicely and drag it to the store. On top of it all, Karcher backs this unit with a 3-year warranty for added value for money and peace of mind.

New Smart Control Update for 2021

The first connected pressure washer. Our Smart Control range boasts cutting-edge technology, allowing you to control your pressure setting using the Karcher Home & Garden app. Switch between the soft, medium and hard pressure settings using the + and – buttons on your trigger gun or you can use your app to easily change the pressure settings on your machine, including the brand new Boost Mode, giving you an extra burst of pressure.

Our recommendation

The Karcher K4 Full Control Home Pressure Washer would be a great addition to most households due to its user-friendly design and excellent overall performance. You can use this pressure washer to clean everything, from cars to driveways and windows to concrete walls. It truly is capable of tackling most cleaning jobs and has plenty of power for the occasional user.

This unit is powerful, comes with two separate lances and you can attach several accessories to it. The thing that makes it stand out from the crowd is its simple operation. In fact, you may not even need to read the instruction manual because everything is so straightforward.

We found a few hiccups regarding the unit, such as the quick connectors for the hose not being able to swivel, but they are quite minor and can be overlooked. We really like the plug n clean detergent system and the LED trigger is a nice feature but this is not essential and does not improve the overall performance. Overall we think this is the best pressure washer for mid-range tasks and a great option for someone looking to invest in a good model but isn’t ready for the expense of the K5. 

If you have a larger garden then we would recommend investing a little more for the Karcher K5 as its worth the extra power and hose length, however, if you like the K4 Full Control Pressure Washer but are looking for a cheaper alternative and don’t mind losing the ‘plug n clean’ system and LED trigger then the Karcher K4 Compact which we review below is the best alternative and has the same power but without the fancy features.

Karcher K4 Power Control High-Pressure Washer with App Control

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 Kärcher K4 Compact Pressure Washer Review

The Karcher K4 Compact Pressure Washer is the immediate brother to the K4 Full Control model. While most of the specifications are the same, the major difference comes in on the compact body and less of the fancy non-essential features. For instance, the K4 Full Control unit operates in an upright position whilst the Karcher K4 Compact machine can is placed on the ground horizontally. It also lacks the LED Trigger gun and plug n clean detergent system.

The Karcher K4 Compact is a super-compact model that is very easy to manoeuvre as it comes with 2 handles and is super speedy to set up with no fuss thanks to the simple click in connectors. It has got all of the power that the more expensive K4 Full Control Pressure Washer has, but at a more affordable price. It is perfect for cleaning patios, walls, fences, small cars and garden furniture. When you combine the high performance, quality build and 3-year warranty it offers excellent value for money.

Pros

• Has a compact design with 2 wheels, 2 handles and telescopic handles that make it easy to transport.
• Can be placed lying flat with no possibility of leaks or short circuiting.
• Supplied with a secure 6m hose attachment which encourages a wide coverage, especially when cleaning driveways and patios.
• Comes with a water-cooled motor which is known to last longer than air-cooled motors.
• Offers storage compartment for accessories such as lances and electric cable.
• 3 year warranty for full peace of mind

Cons

• Like most models the quick connector hose does not swivel so can sometimes try to force your hand left or right, especially when you are trying to clean round a car.

Specifications and Features

• Maximum pressure – 130 bar
• Flow rate – 420l/hr
• Hose length – 6m
• Power – 1.8kW
• Weight – 10.7kg
• Quick Connect hose attachment system
• Includes detergent suction tube for application of detergent
• Dimensions – 57.6 x 39 x 31.4cm

The Karcher K4 Compact Pressure Washer is the compact edition of Karcher’s mid-range units. Combining power and energy efficiency via a water-cooled motor, this machine offers the benefit of remarkable performance, long lifespan and a compact design.

Can be sat upright or lay flat to prevent it toppling over

As we previously mentioned, this unit has a lay-flat design which promotes mobility as it will not be pulled over like the upright-type pressure washers often can. Using the telescopic handle and with the help of fitted wheels, you can move the machine around the job area with little effort and store it away when needed. Onboard storage solution means the gun, hose and accessories can be kept neatly on the unit and ensures they are always within reach.

Obviously, you need adequate pressure for maximum cleaning performance. With a maximum pressure of 130 bar, this Karcher machine will be effective with medium-sized cleaning jobs. Combined with a flow rate of 420l/hr, it can clean cars, bicycles, driveways, and any other area with soft stains.

This unit can draw water from various sources, including water butts, ponds and buckets. Water from a pond, for instance, is certain to contain debris that may damage the pump if it finds access. But thanks to the built-in water inlet filter, that will never happen with this machine. The Auto stop/start function on the motor is another brilliant idea. This function ensures the unit does not run continuously during your cleaning applications.

Simple push fit connectors make connecting the hose easy and fast

Attaching the hose to the body is incredibly easy – simply push the hose into the connector. To release the high-pressure hose, push the sleeve back on the connector. The fact that there is no screwing involved saves you a lot of time. The hose is 6m in length – it’s definitely not the longest available but will give you a decent reach and there is always the option to invest in a hose extender if needed.

Instead of having a detergent compartment, the K4 Compact Pressure Washer is designed with a suction tube which helps keep costs down, this allows you to draw detergent from a separate container. In addition, the pressure washer is supplied with a vario lance so you can select the correct pressure for the job at hand as well as a dirtblaster lance that offers specific cleaning capabilities and is great for removing stains and embedded dirt.

Like all other Karcher models, the K4 Compact Pressure Washer benefits from a 3-year guarantee for full peace of mind.

Our recommendation

From our Karcher K4 compact review, you can tell that it’s a standard pressure washer that would do a decent job for mid-range applications.

With a 1800W motor, maximum pressure of 130 bar, and 420l/hr flow rate, you can expect to clean cars, bikes, garden furniture and fences and get remarkable results. Performance-wise it is on par with the more expensive K4 Full Control Pressure Washer.

Its compact design draws so much attention from those who value easy manoeuvrability, whilst the quick connect system will make it easy to use.

If you are usually involved in some simple cleaning jobs at home, the Karcher K4 Compact Pressure Washer is for you.

Karcher K4 Compact Pressure Washer – The New Upgraded Version

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Karcher K4 Full Control vs Karcher K4 Compact

We hope you have found our Karcher K4 Review helpful, as you can see both models offer the same cleaning performance and will give the same outcome.

All you need to decide is whether you would prefer to splash out the extra expense on the extra features of the Full Control model such as the ‘Plug n Clean’ detergent system and the LED Trigger so you know instantly what pressure setting you have. Or do you prefer the compact lay-flat design and better mobility?

Once you decide this you should have your answer to which Karcher K4 model is the best choice for you.

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Last update on 2024-12-03 / Affiliate links / Images from Amazon Product Advertising API