How much pressure do you think would be needed to clean those windows? Did you have to brush them as well, or just spray and go?
There’s pumps that are made with kynar, buna, teflon, all kindsa stuff that I’m sure would hold up to DI. They hold up to 12.5% sodium hypoclorite, which is much worse then pure water. The only problem is they may be limited to around 300 PSI…
I dont think we needed all we had 1200psi but in places we had to get pretty close to pull some stuff off. This area hadnt been cleaned in about 10 years so pretty nasty
Can clorox bleach leave chalking residue on block home after pressure washing with 4000 psi, if so, what to do
Sounds like a good question for the PWR forum (pressurewashingresource.com).
To address the original topic, which I think is an excellent one and still worth talking about 6 years later:
I think a pure water rinse could be a good add-on without much hassle. What I would do, is softwash and rinse the entire home with regular tap water, and then stick my DI tank before the power washer to go back and rinse the windows. When I’m done with the pure water rinse, I would then bypass DI tank so I can get some regular tap water back into the pump so it doesn’t corrode prematurely. This could be done with a 1/2 or full cube DI tank, or a couple in series depending on your water quality. The nice thing about using DI instead of RO, is that they can keep up with a higher flow rate.
I would probably offer this addon as an intermediate option between a basic housewash, and doing an actual window cleaning with WFP. I would make sure to let them know the results won’t be perfect, but they should be a lot better than just a tap water rinse.
