A few group members have suggested using Jone Cone's cleaning solutions but were unable to say if they are any good. Our computer labs run a fleet of 13 Epson Printers all with a varying degree of obstinance. Weather changes wreak havoc on the print heads (almost more so than our students).
The only cleaning solution we've had overall success with is Piezoflush from inkjet mall, run by Jon Cone.
For cleaning out the printhead this time, I suggest purchasing a set of empty cleaning cartridges with a large amount of cleaning solution. Load the carts, fill them up, and do an initial fill in the printer (they usually send directions on how to do this). Send a few prints through the printer to get the solution to run through, or even just a few power cleanings. Once nozzle checks come out clear, replace the cleaning solution with ink carts and refill the printer.
Next time you need to leave your printer sitting for more than a few weeks, you'll have the cleaning cartridges and cleaning solution - just load those into the printer and let it sit with THAT in the lines rather than ink. This will save your ink lines and printhead from damage and in the long run will save you more money.
Hope this helps
Nick Enghardt
St. Edward's University Advanced Imaging Lab Manager
Austin, TX