Hello,
I’m new to the soft wash scene, I’ve got a 6gpm Hotsy washer and an x-jet nozzle. I was asked to quote a seniors apartment & am wondering what solution would work best to clean off the black gunk underneath the windows. Thanks in advance…!
I’d use 2% SH with surfactant. 10 min dwell, rinse. Reapply if needed, If it’s organic. Be sure to rinse the windows well
test that to make sure it’s organic and not aluminum runoff from the window frames.
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In my area, if those frames are aluminum, it’s runoff from the frames. SH does nothing for it from my experience. I’d do a test spot to see what your getting in to.
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What could take this off then since it’s not organic ?
I’ve use One Restore, it seems to clean so many types of stains and surfaces. I use it straight majority of the time.
Love one restore. Seems like if bleach doesn’t do it on a building one restore will
Thanks guys 
I’ll look into getting some One Restore then and I’ll give that a shot if my SH & Protool Sticky mix doesn’t do anything.
I e-mailed some one at jracenstein and they told me that it was efflorescence/hard water, they suggested that I use this :
Oh man, please reconsider using strong chemicals on window glass. I’m a window cleaner, can’t begin to tell you how many times I’ve had to ‘clean up’ what pressure washers decided to spray on houses and buildings.
I’m a window cleaner before I’m a pressure washer, have been cleaning windows for 7-8 years & am trying to learn more about softwashing.
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I should mention that the black stuff is only on the East side, the West side doesn’t have any of that. Leads me to believe it’s organic ? I don’t know…
Here’s the West side :
Test spot
4 to 6% for that. Dwell and low pressure rinse. May need to hit it more than once. Stucco and effis requires a strong mix. prewet the glass.
Looks to me like organic. You’ll probably need stronger than 2% unless you plan to hit it 5+ times. I’d start with 4% from your x-jet and expect to have to hit it twice.
I just spoke with the building manager & he said that the windows were replaced a few years ago and that the old ones were aluminum sliders.
So I’m guessing the black crap is aluminum oxide ?
So, I went back and did a little test. I put some SH (filled about half) water and a couple oz of ProTool Sticky in my hand held sprayer. I applied that & let it dwell for 6-7 min and then hit it with my pressure washer. Found out that it was organic and not aluminum oxide, very happy with the result !
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Great!
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Can you elaborate? What chemicals would concern you the most? What concentrations would be safe? Thank you!
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