Not harping on about hot water but it's 1 reason why I went hot I do a few days by the sea,I use a good amount of water like 75 on the digital controller with the brush close to the glass so no splashing or over spray. If working by the sea doesn't convince anyone to go hot nothing will they come up perfect everytime and as for talking about first cleans any regular clean by the sea is like an inland clean that's never been done for years,if I went back after a week certain times of the year they would look like they hadn't been done for years.