packed up after a job today and had to get it all back out as water had got into a vent and run dirty water over a pane

. The pressure through the pencil jets sprays up and out when I rinse so I spent more time rinsing and more rinsing. Extra tricky when on 2nd storey. My question is are any of you based in the Northants, Beds (sort of) area that is prepared to let me watch them wfping, established pro's if poss. to give me an idea of how long I should be taking. I'm off out now to finish off. Hopefully hear from someone later.
Thanks
Tom
ps I know about the Ionics roadshows, I'd just like to see wfping in the field type thing