What detergent for a Karcher window washer?

[lifeofsiam]

We have inherited one. I know Karcher do their own liquid, but if you have one, do you get decent results with anything else? Dh just tried with glass cleaner and it's quite smeary.

I use a drop of washing-up liquid and a dash of white vinegar in water, wash windows with this and microfibre cloth (or use long-handled mop), then hoover up liquid with the Karcher. May need to wipe round edges, sills with dry cloth afterwards. Wash out the Karcher reservoir bottle.

You only get a small bottle of the solution with them so we find hot water with a tiny drop of washing up liquid leaves the Windows pretty clean.

Thank you both

We use Karchers own detergent liquid and it's great. Our windows come out looking spotless without any smears.