When should you refill ink?

Here, the sooner the better, because some printheads need ink for cooling.
If the ink coolant is missing, the print head can overheat and the corresponding nozzles will break down. If a print head is clogged or the ink is running low and the first dropouts are noticeable, the time has come to refill the ink.

To make a dried up sponge or a dried up print head again passably is a very time-intensive work. If it does happen, our nozzle cleaner for printheads will help you.

In a nutshell: dry operation damages the printheads and shortens their lifetime. So... Refill ink as soon as possible.