Washing your car in Cape Town has proved to be rather difficult due to the ongoing drought for well over a year now. But, I worked out how to use my Karcher high-pressure clear in gravity feed mode with rainwater that I harvested.
I started harvesting rainwater at our home as an experiment last year with some success. We have 120L plastic refuse bins, positioned at each of the 4 down pipes from our roof. Using a cable tie, I fastened a piece of shade cloth at the ends of the down pipes to catch leaves and other debris. This has resulted in ample amounts of clean rainwater.
[photo of bin full of rainwater]
I was desperate to make use of this water and finally use my Karcher 2.21 high pressure cleaner again. I found a video which showed the use of an alternative water source with a high pressure cleaner by Karcher UK. [https://www.youtube.com/watch?v=DOXOOR1GEu8]
This was my first attempt at using an alternative water source and the gravity feed mode. And I am certain there is room for improvement.
Preparing your water source
I have a 10L watering can which has quite a fine filter to catch any small particles the shade cloth missed. After filling my watering can with rainwater from the bin, I used a funnel to fill a 25L water bottle.
Improvement: an extra step of filtration at this point would be beneficial. You want to prevent any small particles getting into my high-pressure cleaner. A cheap hack would be to use a piece of stock over the spout of the funnel.
Connecting the water source
With our garden hoses all but useless due to the current water restrictions, I cut off a piece about 2m in length. Then I filled the piece of hose with water and blocked both ends with my thumbs to reduce any air pockets. I plugged the end of hose with the connector into the high-pressure cleaner as you would normally do.
michaelthorne
commented
6 years ago 
Washing your car in Cape Town has proved to be rather difficult due to the ongoing drought for well over a year now. But, I worked out how to use my Karcher high-pressure clear in gravity feed mode with rainwater that I harvested.
Water Wise
The recent rainfall over the Western Cape has pushed the storage levels in the dams to 31% (as of 8/6/2018). [http://www.capetown.gov.za/Family%20and%20home/residential-utility-services/residential-water-and-sanitation-services/this-weeks-dam-levels]
I started harvesting rainwater at our home as an experiment last year with some success. We have 120L plastic refuse bins, positioned at each of the 4 down pipes from our roof. Using a cable tie, I fastened a piece of shade cloth at the ends of the down pipes to catch leaves and other debris. This has resulted in ample amounts of clean rainwater.
[photo of bin full of rainwater]
I was desperate to make use of this water and finally use my Karcher 2.21 high pressure cleaner again. I found a video which showed the use of an alternative water source with a high pressure cleaner by Karcher UK. [https://www.youtube.com/watch?v=DOXOOR1GEu8]
I then contacted Karcher South Africa who pointed me to the Water Wise article on their website. [https://www.kaercher.com/za/water-wise.html]
The setup
This was my first attempt at using an alternative water source and the gravity feed mode. And I am certain there is room for improvement.
Preparing your water source
I have a 10L watering can which has quite a fine filter to catch any small particles the shade cloth missed. After filling my watering can with rainwater from the bin, I used a funnel to fill a 25L water bottle.
Improvement: an extra step of filtration at this point would be beneficial. You want to prevent any small particles getting into my high-pressure cleaner. A cheap hack would be to use a piece of stock over the spout of the funnel.
Connecting the water source
With our garden hoses all but useless due to the current water restrictions, I cut off a piece about 2m in length. Then I filled the piece of hose with water and blocked both ends with my thumbs to reduce any air pockets. I plugged the end of hose with the connector into the high-pressure cleaner as you would normally do.