The Epson R3000 is sold as a desktop printer. But really, it is the smallest PRO printer that Epson manufacturers. Desktop printers have always been printers in which cartridges sit directly on the print heads.
PRO printers have ink tanks that are larger and sit on a location that does not move with the print head. Instead the tanks are connected to the print heads with long ink lines that are attached to ink dampers. The ink dampers act as both filters and as temporary ink reservoirs that hold a quantity of ink that is printed and then replenished during printing by an auto head clean.
The reservoir replaces the ink cartridge that would otherwise sit on the print head. It all makes sense. But, this R3000 is not a desktop printer and it acts like a PRO printer. In fact, the R3000 uses the Epson PRO 3880 print head and has very similar dampers as the PRO 3880. The R3000 has ink lines. In short - the R3000 has everything the PRO 3880 has except for the PRO printer utilities.
Epson left these utilities off the R3000 and the new 4900, X890 and X900 printers. As a result - a customer can not actually perform a POWER CLEAN which moves considerable amounts of ink through the ink lines, damper and print head to clear stubborn clogs or to clear air in the lines. The alternatives that Epson supplied can actually fry the print head by over-heating it.
So, you want to avoid getting yourself into troubles you can avoid.
Refillable carts have no way of knowing how much ink you put in them
That's right! The chip does not actually measure the ink in the cart. It only measures how much ink has been printed or used during cleanings from a 100% full cartridge. The chip can ONLY be reset to 100% full. If you fill the cart part ways and reset the chip - the chip still reads 100% full. If you fill the cart part ways and you reset the chip - you WILL run out of ink prior to the Epson Status Monitor alerting you to an empty cartridge. The result is that you will intake air into the ink lines that you will not be able to remove using the utility as supplied by Epson.
If you do not keep the carts in sync with how much ink the chip thinks is in them - you will run out of ink and your printer will suck air into the ink lines. We have had three customers in the past week allow their R3000 printer to run out of ink. The only way to avoid this is to completely fill the cartridge with ink and reset the chip at the same time.
You must pay attention to how the chip works. If you forget to fill the cartridge but remember to reset the chip - the chip will read 100% full while the cartridge is not 100% full. If you put this cartridge into your printer and begin printing - it may be a week or more before the ink that is in the dampers and the ink lines are completely used up and air finally enters the print head.
No amount of head cleanings will remove the air and replace it with ink. The pressure within the air filled ink lines is far too great - and it would take about 70 head cleanings in normal use for fresh ink to reach the print heads. If you have not heard by now - performing repeated head cleanings on an Epson R3000, 4900, 7890/9890, and 7900/9900 will either permanently clog the print head or fry its electronics.
How to remedy an R3000 that has air in its ink lines
First of all, you need to identify this as the problem and you can check the ink lines in this model even if its difficult. There is a chance that the cartridge may have been allowed to run dry by one operator and you are using the printer with a filled cart. A week or more may lapse between air entring the top of the ink lines and exiting the print head. Certainly it takes 10 sheets or more. So identify that is either the problem or the possibility.
Do not perform any form of head cleans or powerful head cleans. The only way to eliminate this air is by using the Epson R3000 ADJUSTMENT PROGRAM (ECC) Ver.1.0.1. It is available from 2manuals.com at this link location for under $20.00 This is the same great Epson software that its technicians use to fix your printer. It can reset your waste pad counter and do all kinds of wonderful adjustments.

You will need to use it to perform the INK CHARGE. What the INK CHARGE does is the same thing that happens when you first installed your printer and turned on the On button. The printer goes into an 8 minute cycle of using its capping station and pump to suck ink from the newly installed tanks through the ink lines and dampers and into the print heads. It removes all the air in the system and replaces it with ink.
This software runs only under Windows but will run on Windows for Mac using Parallels. It works!