I have been using a wfp for around 2 years now so I thing I know the ins and outs. The problem now is that I have just taken over of a complex that some window cleaners have done before but never did the frames. At the top of the frames are some vent and I always clean over the vents without any problem. I know lots of window cleaners dont because it like opening pandoras box! I Just tell the customer it take 2-3 cleansto get on top of it and they are fine.
BUT this time after the first and second clean their are still waxy/greasy runs on the window, and no matter how much I scrub their are still greasy runs. I just know after the 3rd, 4th even 5th and beyond the waxy lines will still be there.
I suspect its my brush head is past it sell by date, Ive heard somewhere that the tips of the brissles do the work like a tooth brush. Has anyone else experienced this? Id appreciate any advice.