Sometimes we take for granted modern inkjet printers because of their competence and reliability. Modern printers, though, are incredibly complex machines, particularly with respect to the printheads. Each printer and its printheads is designed for a particular range of environmental conditions, including temperature and humidity. For most home printing situations, humidity is most likely to be the issue as temperature ranges in most houses stay within a relatively tight range. Epson printers (which is what I use) have a recommended humidity range of 40% – 60% for optimal operation.
So, does this really matter in the real world? Generally speaking, yes. My personal experience, and that of many others, is that operating one of these printers outside this range (particularly at lower humidity) can result in much more frequent clogs and, as a result, wastage of ink from nozzle cleanings and wastage of both ink and paper from ruined prints. (to read the full article, please go here).