Today at Goodwill I bought a groovy old GE electric iron, black plastic/shiny stainless steel, cotton-covered cord, nice and heavy so it presses the clothes without you having to push. It looks to be in great condition, was probably kept in someone's closet unused for quite some time. BUT there are some dusty lint balls in the steam holes on the sole plate -- how should I clean them out? This doesn't have "burst of steam" option. I don't want to poke at them with a pin and force them in further. Would it be a good idea to put white vinegar in the water hole and let that steam itself out?