You're supposed to clean an iron?
Mine is 10 years old and I've never cleaned it. Hasn't spit out any nasty stuff yet, so maybe I'm safe!
I don't know, maybe the new ones have continuous clean? I would have to go look what brand mine is, I don't remember. Of course, I bought that iron a long time ago - 1974 or '75. Self-cleaning was a fancy feature back then.
Have a look at your iron and see if it has a super hot setting for cleaning. It isn't just that it might spit out something nasty - unless you have very soft water, it is likely filling up with mineral deposits that will clog up the vents. That's why most steam irons back then required distilled water - no minerals.