No, they only burned books.

I don't have my copy handy (forgot to shelve it where it belongs after the last time I read it), but at one point Clarisse asks Montag if it's true firemen used to put out fires and he tells her that's not true, that houses were always fireproof and firemen always burned books.

Also, later, in a discussion with Beatty, they review the rules of firemen written by Ben Franklin (or supposedly written by him), and there is no mention of putting out fires.