This is the third time that this machine has developed a problem with a loss of pressure. I would have thought, seeing all the previous reviews, that Karcher would have tried to remedy the inherent problem and improve their reputation. They haven't done so. A waste of good money.

I have purchased K5 website is horrendous to order. Went to use it for the first time and there is water gushing out of a split fitting. This product has not been tested at all. It must of been a return and resent out. No quality control at all. Trying to return that’s a laugh in itself. You log on your account select your order and reason for return. You get an automated message back - to log back on your account and do the same again this is the only way they can process. Done this twice I have asked them to call. They haven’t. The service and process is disgusting. I wish I had gone off other reviews and not purchased one. When I eventually get this sorted I have to stay in whilst they pick up wait another week for a new one. It’s pathetic. DO NOT BUY FROM THE OUTLET

Had this machine 4 yrs, repaired twice for loss of pressure and now failing again. Complete waste of money. I was told that the diaphragm in the pump is made of plastic and this is the reason for the failure. I would have thought that Karcher would have been concerned about their reputation but clearly not so.

I bought this machine about 3years ago at first I thought it great,but now it is only good for cleaning my car and not the slabs I initially bought it for,as it seems to have lost the pressure it had in the first place. For what cost I would have expected to have lasted longer.Will be looking for a more powerful petrol one next! 

Have had a Karcher K5.55 for a couple of years now - it is a complete disaster. It has never worked properly and the supplier has been claiming we have overused it- We have only used it for domestic purposes. I will never buy another Karcher product. I was offered an equivalent Stihl for the same price- bad mistake - should have bought a Stihl! The Karcher soon lost power due to a plastic head distorting!

Started 'pulsating' at 367 days old. Service centre (Karcher Store Consumable Products, Newtownards, County Down) didn't want to know until, as above, my wife contacted Karcher to find there was a 2 year warranty! They should have told their service centres. However, at about 2.5 years it failed again. I replaced the cylinder head (apparently the most common fault) to no effect. Replaced as many 'o-rings' as I could fing - you guessed it! Anyone want a brute of a motor to hold a large door open? I should have read more reviews and I hope this helps others avoid problems. DO NOT BUY KARCHER - I won't!!!!!

Went back to karcher 3 times with pressure loss.After only a short time would have same problem again.Would never bye another.Stay away from Karcher.

The pulsing started last summer when the machine was 18 months old. The paperwork said 12 months warranty. In disgust I put the machine away with intention of scrapping it then I had a flush of desperation and emailed Karcher. Their response was: Thank you for your recent email, what date in January did you purchase the unit, any machine purchased after the 1st Jan 2011 came with a 2 year warranty, if the machine is still in warranty we can arrange collection upon receipt of the receipt of purchase. I was in luck so I delivered the machine to their recommended local agent. 4 weeks later I collected the machine and the agents parting remark was to the effect of 'don’t let the frost at it again’. This prognosis was confirmed by Karcher when I again emailed them requesting a status of warranty (12 more months) and what faults were found (frost damage). The thing is the machine failed in the middle of summer. During the harsh winter of 2012 the machine spent its time in our laundry much to my wifes annoyance, I spent a lot of money on the machine afterall and the paperwork does stress to keep out of frost. I have yet to try the machine as I only picked it up on Monday. I just hope it works. Would I recommend Karcher???????

Brought this pressure washer about 18mth ago working fine at first about 4 months ago it started losing pressure then the motor starting pulsating. its that powerful you can put your hand in front of the lance without it being a problem what a load of rubbish never buy another one.

I've had the same problem with 5.55s. The first lasted some time but reeated repairs were unable to fix problems. When it finally failed, there was an offer on a new one with all of the tools. It failed during warranty and Robert Dyas replaced it completely. It is only about 18 months old now and will not switch on. I won't buy another, whatever the offer.

I`ve had 3 Karcher pressure washers and I should have learnt my lesson by now. Every one has developed the same problem and every time Karcher fob you off saying it`s not an inherent fault. My last one cost £200 (k5.55) and lasted 18 months of which I used it approx 18 times. They e-mail you the same air lock rubbish every time. They make out they are one of the better brands but don`t believe it I will never ever buy one again.

THE WASHER WAS EXCELLENT UNTIL IT BROKE AFTER APPROXIMATELY 25 HOURS NORMAL DOMESTIC USE (AND WAS OUT OF WARRANTY). KARCHER ACCEPTED NO RESPONSIBILITY WHATSOEVER AND ITS APPROVED REPAIRER TOOK APPROXIMATELY 6 WEEKS TO GET IT REPAIRED (SUPPOSEDLY DUE TO THE DELAY IN RECEIVING A KARCHER SPARE PART. I WILL NOW NEITHER BUY OR RECOMMEND KARCHER PRESSURE WASHERS.