I have had an Epson R1900 for several years and the only time I had to bring it in to a technician for head cleaning was after I was away from home for a long time and our house sitter had powered off the computer and the printer sat idle.
Usually, even if not doing frequent printing, the Epson does a self cleaning every time the computer (iMac - 10.6.8 OS) wakes up from sleep. I am now dealing with a really hard to clean head clogging (printer, not me) and I realized that i have not been hearing the familiar printer self cleaning that I used to hear at least once a day. I hope I have this terminology correct, please excuse me if I am not being as clear as I should be.
Any thoughts as to how to get the Epson back to its self cleaning operation? I have been unable to find any information on this in manuals or Google search.
Thank you!!

Thanks Fred for the reply. That was the first thing I did and it didn't seem to help. Also tried redownloading the printer driver. Can't think of anything else to try. Maybe I'll try to get in touch with an Apple techie.

Print a nozzle check and that will settle  the matter.
Terry