Blackman Plumbing Supply Co. (Bethpage, NY) elected Robert Mannheimer president. Mannheimer succeeds Richard Blackman, who is retiring and relocating to Florida. Blackman will continue to serve as chairman of the board of directors. Mannheimer has been with the company for 16 years and currently serves as the chief operating officer. Mannheimer formerly served as Blackman’s director of finance and administration. Prior to joining the company, he was vice president of Harmon Kardon and JBL Consumer Group.