Just got my WCW backpack deal and have been trying to use it on my own house, which has 6 windows. The windows and frames haven't been cleaned in a few months so I could try getting used to using it on windows that haven't been cleaned in a while... So from what I have read on first cleans you should turn the pressure right up as high as it will go, do the frames, then do the tops, then rinse, then do the window below, then rinse and do the same down stairs. I wouldn't be using it for down stairs for proper jobs, just getting use to it and experimenting. But so far to do my whole house I have managed to use well over the 22L the back pack holds, probably closer to 30+L. Is this normal or am I going over the top with how much am rinsing etc?