Nothing in this part shall be construed to provide that a limited licensed plumber is a contractor. It is the intent of this part to provide that a limited licensed plumber is subject to the jurisdiction of the board solely for the purposes of licensure and disciplinary proceedings. No limited licensed plumber shall be authorized to use the appellation “contractor” or any other designation that gives or is designed to give the impression that a limited licensed plumber is a contractor unless the limited licensed plumber also holds a valid contractor's license issued by the board.