 Re: reason for closing the vavle of the waste ink bottle when not printing
There are several posts where people talk about cleaning the capping station at night and putting cleaning fluid in it. In the morning, most of their ink has been sucked out of the bottles and the waste bottle is full. This can happen by the cleaning fluid causing a suction when the print head is capped as the cleaning fluid goes down the waste tank. Thus, you lose ink. If you cut the valve off to the waste tank, then you don't have to worry about the suction occuring.
What is described above is not something that happens to all printers. In fact, I would imagine that it only happens to a small percentage of the total printers out there. But when it comes to you losing ink or even worse, coming in the morning to see the waste bottle overflowing into your printer or table... it is not good. So for the extra little step, most people find it worth it. Just make sure that you reopen it before printing.
Mark | 
