Everything comes to he who waits.....
As mentioned above, I have an epson r1800 ink jet printer, and it was powered down on July 20th. On Sunday evening, 26th November, I thought it may be time to get it going again, a period of no use of about 20 weeks, I guess.
So, what to do? Turn it on, of course. It does its usual shuffle, put in a sheet of paper, print nozzle check, nothing. Out of all those little nozzles, not one fired. A couple of ink clean cycles - one of the blacks decides to play, firing on about 60% of its jets.
I remember someone saying about using 'Windex' on the foam pads before shutting the printer down, - I didn't do that, back in July. Googling for r1800, repair, and so on got me to the 'inkrepublic' web site and others, which went into detail about squirting cleaning fluids down the nozzles, etc. Now, I have a continuous ink system from 'Fotospeed' in the UK, running their pigment inks, so I have a bit more control over the ink flow situation, compared to cartridges. I can raise the external tanks to increase the ink pressure, I can shut off an individual ink line, if that one is flowing OK, saving ink on continuous cleaning cycles, and I can see the ink going through the tubes in a cleaning cycle (if there are air bubbles in it, like now).
Anyway, as I was not bothered about the time taken to get the printer working, and as I didn't want to be messing with the ink, I simply dribbled some clear window cleaning fluid (being in UK, we don't use 'Windex', I used some cheap stuff called 'W5', which looked like a weak solution of washing up detergent and water) onto the foam pads and turned the machine off, leaving it overnight. The next day, after a few cleaning cycles I had yellow, magenta, cyan and the two blacks running pretty good, but not a squirt from the red, blue or gloss optimiser. More soaking of the foam pads, power off for a few hours, clean cycle a couple of times and nozzle check, same result. Trying to print large blocks of the faulty colours gave a striped effect, and it was not possible, after the icc profiling, etc. to hit the exact cartidge colour. However, last night, the nozzle check showed some spots (about 3%) of the red and blue heads firing. I guess that was after a half a dozen of my soak, wait, clean, test cycles. Today, after another long overnight soak, all jets firing.
My conclusion is that if the heads get blocked, then it can be simple to unblock them, if you are patient. It can be done more quickly, by using special fluids, some dismantling, etc. but in this case, it was not required. Of course, this was a blockage caused by the ink pigment carrier evapourating, not by paper debris, or dust, whatever. I read, that if you use pigment cartridges, then the dye based cartridges are a good substitute for cleaning fluids, but I think that maybe 'Windex' is cheaper.
Best wishes,
Ray