Greetings, fellow LL readers. I'd been reading w/some concern the various topics on Epson 4900's clogging ever since I got my first unit a couple of years ago. Currently on the second unit after the first one suffered a power supply failure necessitating a return to Epson and replacement w/a so-far reliable refurb. I'm a fairly light, 'hobbiest' printer, mostly for personal enjoyment, and that of my co-workers. I don't have the option of using a whole-room humidifier as the unit is home-based, and I have quite an open floorplan in my home, thus in order to humidify the printer environment, it would require a humidifier capable of humidifying about 1500 square feet total. So I looked for local alternatives that might keep the humidity in the immediate printer environment 'moist' enough to prevent clogs. I settled on an extremely 'low-tech' approach of a plastic food storage container and a large utility sponge. This is placed inside the printer, and I have a sticky-note covering the power button to remind me to remove it before powering up the printer. Using this 'system', I've never had more than the occasional, minor clog in various channels (never more than one at a time, but no one channel that predominates, or that is immune) that are always remedied by doing a paired - cleaning of the affected color. I also print at least a test-print every 3-5 days followed by a nozzle check to confirm 100% clog-free status. I've never had to do a deep cleaning, and never had more than about a 1/16" gap in one line of any color. Darn those yellow ones are hard to spot though!
As far as the two week vacation, I kept the printer covered using a custom printer cover ordered from Digital Deck Covers, one of the many on-line companies that make these sorts of things. I'm not specifically endorsing this one, I think they'd all be about the same. I filled the container about 2/3 full of water, and when I returned after two weeks and did a nozzle check I had ZERO gaps in any color! The water had evaporated from about 2/3 full to just under half-full in the container. Mind you I'm in the US Pacific Northwest, so we have a pretty mild environment here. Home thermostat was set to 65 degrees for heat, and I have no air-conditioning in the home.
These containers are widely available in most grocery stored in the plastic wrap/aluminum foil sections, and the sponges can be had in the cleaning supplies area. Total investment a few $US. Well worth it in my mind for the added peace of mind I feel.
I'll admit, I am exceedingly careful when removing/replacing the water-filled container, I'm not sure what if any vital components lie beneath that section of the printer that might be affected if some water spilled through there, but I think it's just the second ink waste tank...but I don't feel like testing that theory, either!
Now...would my result after the vacation been any different w/out this? Who knows. But I'll go into future vacations with a bit more ease of mind following this process. Hope you find it useful.