I have a continuous ink supply on my R33 which has been working well, but of late the black feed has been not performing resulting in many head cleans to get it to pump through. Why should this this be I wondered Then I though is it because................. I have also fitted an external waste ink collector and being a skinflint have been pouring the resultant out flow back into the black pot. A possible cause do you think?
Highly likely, as the ink in the waste collector has probably thickened having been exposed to air. Adding this to the reservoir has knackered the viscosity and probably done the print heads no good at all.
Obviously dependant on atmospheric conditions, but even water based inks in an open container will be subject to some evaporation as well as being open to dust, pollen and other airborne contaminants. Print heads don't need much to clog them.