Kärcher K5 review
Start with the thing most people get wrong about this machine. Don’t buy a K5 for cars. A hatchback does not need 145 bar, and if you’re standing in front of the shelf thinking the bigger yellow box will get the paint cleaner, it won’t. It’ll just cost you another £170.
Buy the Kärcher K5 Power Control Flex if the drive is long or green, and you already know from experience that 8 m of hose leaves you walking the trolley to a new spot halfway through. That’s the whole case for it. At £339.99 it’s a driveway machine, and for the usual house the default buy is still the K4.
Kärcher K5 Power Control Flex
145 bar, 500 L/h and 10 m of PremiumFlex hose, on a 2.1 kW water-cooled motor. The long-plot buy, and only that.
- Full specification
- The review
- Which carton
- The T 5 head
- Cars don’t need it
- When to buy something else
- FAQs
Kärcher K5 Power Control Flex specification
| Specification | Figure |
|---|---|
| Pressure | 20 to 145 bar |
| Flow rate | 500 L/h |
| Area coverage | 40 m²/h, Kärcher’s own figure. Treat it as a catalogue number rather than a promise about your slabs |
| Hose | 10 m PremiumFlex, coiled on a hook rather than an internal reel |
| Motor | 2.1 kW, water-cooled |
| Weight | 12.4 to 13 kg without accessories |
| Gun and lance | Power Control gun with Vario, plus a dirt blaster |
| Carton number | Read 1.324-702.0 on the box to be sure you have this one |
| Price | £339.99 |
What you’re actually paying for
The headline is 145 bar and the headline is not the point. Fifteen bar over a K4 changes almost nothing you’d notice on a panel or a slab. What changes the afternoon is 500 L/h against 420, because flow is what carries loosened dirt off the surface instead of pushing it around, and 10 m of hose against 8, because that’s two more metres of standing still.
Put those together on a 30 to 40 m² drive, north-facing and green every spring, and you get a machine that finishes in one session rather than a stop-start afternoon of repositioning. Kärcher quotes 40 m²/h for coverage. Treat that the way you’d treat any catalogue figure, as the number from a good day rather than the number from your slabs in March.
The 2.1 kW motor is water-cooled, which is the part that matters if you’re running it for an hour at a time rather than in ten-minute bursts. The PremiumFlex hose stays supple when it’s cold instead of springing back into coils. Be clear about one thing though: it coils onto a hook, not into an internal reel. If a reel is the feature you came here for, this is the wrong machine and you should look at the mains hub instead.
Buy this Flex version rather than an older stiff-hose K5. The hose is a large part of what you’re paying for, and the cheaper cartons give it back.
Buy it for
- A long or green UK drive, roughly 30 to 40 m², north-facing and mossy
- A hose run that already has you dragging a shorter machine about
- 500 L/h, which is the genuine upgrade over a K4
- Cars and that drive, rather than cars on their own
Skip it if
- The jobs are cars, bikes and a normal patio, which is a K4
- The bay is short and 8 m of K4 Flex already reaches
- There’s no outdoor tap or socket, where a lead is the problem and a bigger pump isn’t the answer
- You already own a working K5, in which case buy a head rather than a second pump
- You came looking for 180 bar, in which case read K5 vs K7 first
Which carton you’re looking at
Kärcher sells the same K5 in more than one box, and the differences are accessories rather than pumps. Some cartons include a T 5 patio head. That’s the same Flex machine with a head in the box, not a different or better washer, so treat the choice as whether you want the head bundled and price it accordingly.
Two other names turn up on the yellow shelf and neither is the buy here. Kärcher UK has listed a K5 Classic at £249.99, and a K5 WCM Flex eco!Booster at £299.99. They’re footnotes to this review rather than alternatives, and the Classic in particular gives back the hose that makes the Flex worth having.
Car and Home bundles exist too. PriceSpy has shown those kits from about £359, and there’s a B&Q listing worth checking if a bundle is what you want. Look at the current tile rather than trusting any figure quoted on a review page, this one included.
The T 5 is a head, not a second washer
The T 5 is a 280 mm hooded patio head that fits K2 through to K7. It starts from about £55, and it’s available at that price, with Screwfix at £58.99. It’s also carried by Wickes and sold direct. Read 2.644-084.0 on the box.
Three things worth knowing before you buy one. It is not the small T 1 that ships in a K2 Home box, and the difference on a terrace is enormous. Neither the T 5 nor the T 7 clips onto a Bosch or a Nilfisk, because the gun fitting is a Kärcher one. And the T 7 Plus, which adds a corner jet, fits K4 to K7 only and starts from about £75.
The mistake to avoid is buying a machine to get a head. Don’t buy a K7 just to clip a patio head onto it, and if you already own a K5, buy the head on its own rather than a second washer. Our patio head guide covers the sizes properly.
Cars don’t need this machine
You can wash a car with a K5 and it’ll be fine, as long as you use it sensibly. Drop the Vario right down for paint and glass, and open it up again for block paving. Keep the dirt blaster for paving and nowhere near lacquer. Kärcher’s own advice for vehicles is a flat jet at a minimum of 15 cm from paint and 30 cm from tyres, and that’s a sensible floor rather than a target.
None of that is a reason to buy one. Everything in that paragraph is equally true of a K4 that costs £170 less. If soap is what you’re really after, a dedicated FJ 10 C foam jet runs about £30 to £33 and will change your car wash far more than 15 extra bar ever will. The full order of work is on our car guide.
When to buy something else
Buy the K4 if the drive isn’t the job
The default house buy is still the K4 Power Control Flex, at around £169 with 8 m of Flex hose. It handles cars, a short bay and a normal patio without complaint, and the £170 you’d save is most of a very good foam setup and a patio head. If you’re genuinely torn, our K4 vs K5 comparison is the page to read, and there’s a full K4 review too.
Buy cordless if the socket is the problem
A K5 needs an outdoor tap and a 13A socket within reach. If either is missing, a bigger pump doesn’t fix it, and running a lead out through a window every time gets old quickly. A cordless machine draws from a bucket and goes where the mains can’t. Petrol only comes into it after you’ve properly ruled out getting a lead to the spot.
The K7 is for a much bigger plot
If 10 m of hose still leaves you short, the honest jump is petrol rather than a K7, because the K7 typically ships with a similar hose length and won’t solve a reach problem. Go up to a K7 for plot size and nothing else. Our K5 vs K7 comparison draws that line, and the Kärcher hub puts the whole range in order.
One more time, because it’s the mistake people make. The step from a £169 K4 to a £339.99 K5 is about £170. That’s a lot of money for 15 bar you won’t use on a car. It’s reasonable money for a 30 to 40 m² drive you clean twice a year and currently hate doing. Which of those two sentences describes you is the whole decision.
FAQs
Is the Kärcher K5 worth it?
Yes if the drive is long or green and you’ll genuinely use the 10 m hose and the 500 L/h. No if the house is the usual one. At £339.99 the step up from a £169 K4 is about £140 to £170 depending on what you pay, and that’s a lot for 15 bar on a car. It’s reasonable for a 30 to 40 m² plot you clean twice a year.
Can I wash a car with a K5?
Yes. Use the wide Vario setting, keep your distance, and keep the dirt blaster off the paint. Kärcher’s own guidance is a flat jet at a minimum of 15 cm from paint and 30 cm from tyres. But cars do not need a K5, and nothing about washing one is a reason to buy this over a K4.
K4 or K5?
K4 unless there’s a drive. The pressure difference is 15 bar and it isn’t the point. What you’re buying is 500 L/h against 420 and 10 m of hose against 8, which only pays back across a 30 to 40 m² area. For cars, bikes and a normal patio, the K4 does the same work for roughly half the money.
What does Flex mean on a K5?
It’s the hose. A Flex carton comes with PremiumFlex, which stays supple in the cold rather than curling back into coils every time you set the gun down. On a 10 m hose that matters more than it sounds. Buy the Flex rather than an older stiff-hose K5, because the hose is a real part of what you’re paying for.
Does the K5 have a hose reel?
No. The 10 m PremiumFlex coils onto a hook on the body rather than winding into an internal reel. If a built-in reel is the feature you’re shopping for, this is the wrong machine and you’d be better off looking across the wider mains range.
Some boxes include a T 5. Is that a different K5?
No, it’s the same Flex machine with a patio head in the carton. Price the bundle against the machine plus a head bought separately, because a T 5 on its own starts from about £55. If you already own a working K5, buy the head rather than a second washer.
Should I get a K7 instead?
Only for plot size. A K7 is too much machine unless the land is genuinely large, and if your problem is that 10 m of hose won’t reach, a K7 typically ships with a similar hose and won’t solve it. At that point the honest answer is petrol rather than another mains machine.
The short version. Buy the Kärcher K5 Power Control Flex at £339.99 if the drive is long or green and 8 m of hose has already let you down. Buy the K4 for everything else. Don’t buy a K5 because of the car, don’t buy a K7 unless the plot is huge, and if you just want the patio head, buy the head.
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