I have been ironing for about 60 years and I have NEVER knowingly used distilled water in an iron and my irons last for years. I periodically fill my iron with white vinegar, let it sit and heat well, then hold the iron so it steams profusely. I push every button that pumps water through the iron. Then I empty the iron, fill it with cold water, and do the same thing all over again. If I still smell vinegar, I rinse with water a second time.