Karcher’s WD 4 came to the test bench promising much in terms of power, practicality and versatility, so we wanted to put it through some rigorous testing. To our standard hard parquet floor, carpet, edge, wet spill and water draining tests, we tracked our builder through a kitchen rebuild project, cleaning whatever hit the floor.

How well does the Karcher WD 4 clean hard floors and carpet?

First off, we tackled aged parquet floor with plenty of cracks between the soft-wood blocks and a test area close to a hard edge. A generous amount of talc and carpet refresher powder mix went down in the test zones. A little too generous for the Karcher perhaps? Certainly not. One slow pass over the area using the main floorhead with its brushes attached was easy and gave us a near-perfect clean with a tidy result right up to the skirting edge. There were a few grains leftover, particularly in the deeper cracks, but the Karcher’s outstanding suction meant they too were gone in a couple of subsequent passes.

Used as a daily driver, the Karcher makes for bulky cylinder cleaner but there is no denying its cleaning efficacy. The 1000W motor is 200W+ more than any new dry-only vacuum cleaner and that pays dividends in sucking up dust and dirt deep from within the carpet pile. Most of our talc/freshener powder mix was dispatched from the deep-pile test carpet in a single pass and the floorhead was fairly easy to manoeuvre despite the high suction power. The floorhead design is great for getting close to skirting edges and that suction power left little daily dust little behind.

Out in the workshop, the Karcher continued its mission to impress us at every turn. It did a great job at pulling in all kinds of DIY spoils, including wood chips, thick dust and pieces of rubble. Our kitchen is currently a building site and the Karcher turned in pro-level cleaning results in this challenging environment of deep plasterboard dust and brick rubble. We started to come to the conclusion that the WD 4 would pick up just about anything that would fit down the hose. This wet and dry superstar is an excellent option for those who have a workshop, garage or hobby room and is suitable for cleaning out the car too.

Thanks to the onboard accessory and cable storage, smooth wheels and well-positioned carry handle, transporting the Karcher from room to room is a breeze and it is easily pulled around by the hose on flat surfaces. Emptying the bin is as simple as popping off the top motor unit and pouring the contents out, and the universal filter certainly saved a lot of faffing about between wet and dry use. That cable is a little shorter than we would like at 5m, but that is just about all we can criticise.

How well does the Karcher WD 4 clean wet spills?

With the innovative wet/dry filter, switching to wet cleaning is as simple as removing the fabric dust bag. If you hadn’t been using that for dry cleaning anyway, you can move to a wet area without pausing for breath. On a hard floor, with the floorhead’s rubber blades installed, the WD 4 sucked up a large spilt glass of water in a matter of seconds. It moved relatively easily on the blades and a few strokes over the area left us with almost bone dry tiles. Simply draining half a bucket of water didn’t phase the Karcher either and it transferred the liquid from bucket to bin very quickly.

How well does the Karcher WD 4 clean pet hair?

Pet hair isn’t the easiest thing to remove, especially when it’s deep within carpet fibres and is even more challenging if you don’t have the benefit of a rotating brush bar. Yet the Karcher once again turned in very respectable results. A couple of passes over our dog-loved red rug left it spotless and pretty much hair-free. On the down-side, the floorhead’s carpet brushes did tend to hang on to a lot of the hair, so a quick brush clean will be required before moving onto the next area.

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