Kärcher Window Vacuum WV2 review: A versatile cleaning gadget for streak-free windows and mirrors

Telegraph

17-04-2025

What is the Kärcher WV2 Window Vacuum?
You may not have realised how much of a household staple a window vacuum can be for cleaning both in and outdoors. But if you routinely struggle with moisture or condensation on your windows, shower screen, or car windshield, this handheld device can be invaluable.
As the inventor of the window vac, it's not surprising that Kärcher was the number one selling brand in the UK last year. While it offers a range of options to tackle everything from condensation and damp to dirty windows, one of its most budget-friendly products is the WV2 Window Vacuum, which topped my list of the best window vacuums.
At £46.80 it is priced in the middle of the market, though you can pay a little more for the WV2 Plus or WV2 Plus N bundle to get the full kit of microfibre spray bottles and additional blades and really get going on the cleaning you might usually leave to the professionals.
JUMP TO:
How we test window vacuums
Firstly, I assessed the level of suction power on the WV2 looking at how successfully it removed any water or condensation from windows, bathroom mirrors and shower screens and my car windscreen. For each surface I tested whether the squeegee blade left that coveted streak-free finish and kept in mind how much I needed to empty the water tank while performing each task.
As window vacs can be used on interior and exterior windows you can end up holding them aloft for quite some time, so how comfortable the device is to hold in terms of its handle size and overall weight is an important factor to consider, too. I also took note of how easy it is to use the WV2 straight out of the box, how long I could use it on a single charge and how long it took to get fully powered up before I could start vacuuming again.
Why you can trust Telegraph Recommended
Our thorough, real-world tests will always help you find the best product. No manufacturer ever sees Telegraph Recommended reviews before publication and we don't accept payment in exchange for favourable reviews, nor do we allow brands to pay for placement in our articles.
All reviews are based on independent expert opinion and our hands-on testing. Visit our Who We Are page to learn more.
Suction power
Score: 9/10
One of the most important qualities of a good window vacuum is its suction power. I used the WV2 to collect condensation across a large window, tackle the steamy mirrors and screens in my bathroom after a long shower and to get a clean finish on my exterior windows (which I usually leave to a professional window cleaner), after spraying a decent amount of detergent or soapy water over them. I only needed to give the WV2 one pass over the surface in question for it to completely suck up any and all moisture, which is far better than some window vacs I tested that needed to go over an area multiple times.
The lack of drips or streaks left by the Kärcher WV2 was impressive, making it incredibly reliable and fast and not just on vertical surfaces. It sucked up spills on worktops and tabletops with ease, too.
Squeegee blade design
Score: 9/10
The WV2 window vac comes with a 28cm suction nozzle squeegee, which is particularly helpful for larger surface areas and jobs. However, you can also purchase a smaller 17cm nozzle separately, which will help you reach tighter spots and corners or get right down to the bottom of a pane of glass.
If you are switching between the two or simply popping the blade back on, you can detach and reattach them in a matter of seconds, which is particularly beneficial if you want to tackle different surface areas in the same room or during your cleaning session.
The blades are what ensure the WV2's streak-free finish over and over again, whether you're swiping across horizontal or vertical surfaces. And once they begin to feel a little worn you can easily slide them off the nozzle and replace them with new ones.
Water tank
Score: 8/10
The standard water tank size for most window vacuums is around 100ml (depending on how compact or large the device is) and it's the capacity you'll find on the WV2. It more than sufficed for my everyday cleaning and vacuuming of condensation. And I got into the habit of emptying it after each use or every few days to stop the water from building up and sitting in the tank for too long.
The tank itself can be emptied easily, either by using the built-in spout which lets you quickly pour any water into a sink without the risk of making too much of a mess, or by completely detaching the tank. This means you can clean it out properly if the water is particularly grubby, which I found especially handy after cleaning my car windscreen.
Comfort
Score: 8/10
The grip on the handle meant I found the WV2 window vac comfortable to use for the entirety of its battery life, which is around half an hour. I have quite small hands but the handle didn't cause my palms to stretch as some of the bulkier models I've tested have. And at 600g, it is one of the lightest options on the market at the moment. Even when its tank is full of water or moisture it didn't feel too weighty, which makes a difference when you start reaching up to higher windows. You can also purchase an accompanying Window Vac Extension Pole to make things that bit easier.
Much like the best vacuum cleaners, some window vacs are noisier than others, but the WV2 only makes a low burring sound. Technically the noise is no louder than 53dB, which is similar to the level of noise you would hear on a quiet residential street or during a normal conversation.
Ease of use
Score: 7/10
While you get a 35 minute runtime once the WV2 is fully powered up, which is about five minutes longer than other models, the Kärcher WV2 does have a considerable charging time. It takes just under four hours to charge fully, so you have to remember to plug it in quite a bit ahead of any cleaning you're planning.
I personally charged it the day or evening before I wanted to clean a number of windows so it was ready to go and tried to remember to put it back on charge when I was done. The LED battery display will also let you know when it's low on battery.
Another slight issue was the stiffness of the power button. I had to press quite firmly and in the exact right spot to turn the window vac on and off, which became a little frustrating and didn't feel as user-friendly as it should have.
Technical specifications
If you've been thinking about investing in a Kärcher WV2, a good model to compare it to is the pricier WV6 Plus version, which also made my list of the best window vacuums.
Should you buy the Kärcher WV2 Window Vacuum?
For those looking to invest in a Kärcher window vacuum, the WV2 is a great entry-level option that gives a streak-free clean on windows, mirrors, shower screens and tiles and happily on car windshields, too. It is also frequently on sale and discounted throughout the year.
Yes, if:
You want a streak and drip free finish on a range of surfaces
You frequently get condensation in your home
You want a quiet and lightweight option that doesn't feel cumbersome
No, if:
FAQs
Can you use fairy liquid on Kärcher window vac?
While you may be tempted to use fairy liquid – or similar washing up liquids – alongside your Kärcher window vacuum, Rossi Salvatore, the retail product manager at Kärcher strongly recommends only using its specially formulated detergents as they are designed to 'ensure the best cleaning results without damaging the product'.
I did try the WV2 with some slightly soapy water on an exterior window, however, and it didn't seem to cause any issues. So, doing this every so often shouldn't be too problematic and lets you tackle dirtier surface areas if you don't have the official Kärcher detergent.
Why does my Kärcher window cleaner leave streaks?
Window vacuums can occasionally leave streaks if you've not used enough detergent or conversely if you've used too much. It's important to regularly clean the suction blade or squeegee to prevent any dirt or grime from building up, which can also cause streaks.
Can you get new blades for Kärcher Window Vac?
Yes, you can purchase replacement suction blades for all of the Kärcher Window Vac models. This set, in particular, is compatible with the WV2 device.
Can you leave a Kärcher window vac on charge?
Kärcher recommends promptly unplugging the WV2 once it is fully charged to maintain the battery health on the device to keep it performing at its best for years to come.