[combat1]

Noticed on a couple of jobs just lately spotting. Never had it before but they were windows which had not been cleaned for a while. I rinsed three times but it couldnt have been enough. Water was 000ppm.
Does the sun make any difference?

[Splash 4 Cash]

I have found if there not a good  flow rate You will need about 4-5 litres per minute  on the glass. Remember we are floating the dirt of the glass.

[Elfyn]

Just as Splash says, but if it's only at the top or at the bottom your pulling dirt/soil off the frame or glazing bar. A quick going over without touching the top bar and a good rinse should do it.

[matty72]

i think all window cleaners leave those spots sometimes, you just cant help it, i think you just need to keep the majority spot free, some customers are a bloody pain though see a spot and just love to complain where as some are mellow and understand might happen occasionally

[Spruce]

Noticed on a couple of jobs just lately spotting. Never had it before but they were windows which had not been cleaned for a while. I rinsed three times but it couldnt have been enough. Water was 000ppm.
Does the sun make any difference?

The problem was most probably the heat. If they dry too quickly the dirt doesn't get chance to drain off as the water evaporates before the process is complete as has be said. If I remember someone who did WFP in Cyprus (I think it was) said that the first thing they had to do was to cool the glass down  before attempting to clean it. And of course, the bright sunshine makes it easier to see the imperfections.

Spruce

[matty72]

yea the heat means more water to get them clean, done a gutter job the other day with customers water, so hot all yhe spots on windows took ages to clean off

[Dean Taberner]

I had the same problem today,

The direct sunlight and heat means that the dirt dries on the glass before it has a chance to run off the glass.

I did a big building and had a walk around after to see that they had dried terrible and had to re do the majority of them again with a higher flow rate.

It distressed me greatly.

Dean.

[VSP Home Care]

Glad you chaps posted this, I had a few spots in direct sunlight yesterday and wondered why, I think you have it right.

[Dougaldum]

also depends on the glass some glass sheets nicely which does not leave spots its the glass thats dose not sheet  leaves spots thats what i find 

[Window Washers]

i simple rule of 000 and good rinsing, now for the 20 tds guys to say its fine apart from direct sunlight ROLLEYES

[birdymiller]

I had poor results on friday on windows that didnt sheet. Glad some of you others had this problem, thought it was just me. I didnt re do windows, did they come up better with a extra rinse?

[Londoner]

It seems to be a common problem with windows in direct strong sunlight.