[EZclean]

6 cleans in with wfp, so i've got a good idea of what its about and how to clean a window, but i've come across 5 or 6 windows on the whole round on different houses, that have runs when they dry.
now the style of window is always the ones with 2 large rectangular openers above a large pane.
i've done everything i can think of to get it right, all the top frame, loads of rinse with pure, scrubbed the middle gap between the openers and rinsed re-rinsed.
then left it, yesterday i actually did that window first, then did next door (semi), then went back and did all the other windows and left it to the last one, then didn't touch the openers, just the pane below.
last time i did it i asked the customer to clean the rubber seals where the openers meet the frame, hoping that if any muck was leaching from there then at least its something else i've tried,
well it didn't work   
its the same for the other 5 or so windows of the same style,

what i can i do differently to solve it, before i do them trad, which i just dont wanna do?

i have excellent results now on the rest of my work and i'm really happy with the system.
water is always 0ppm too.

[Ian Lancaster]

I presume the runs are below the join between the two openers?  Solution: don't put any water on the frame between the two openers :

[prestigeclean]

is there a slight gap in the seal , i had that problem on a couple of windows and that made them run , funny thing is it just stopped after about a year regards alan

[Small but perfectley formed]

If you can get the customers to leave the windows open about 8-10 cm this lets all the water run off but not on the main pane.

[EZclean]

last time i wiped the runs when they had dried with microfibre