Frederick G. Pfannenstiehl has been elected chairman of the board of directors at South Boston-based Mt. Washington Bank.

Pfannenstiehl previously served as vice chairman of Mt. Washington Bank’s board for nine years, and has served on the board since 1970. He succeeds Thomas S. Gunning, who retired from the board Dec. 31 after serving as chairman for the past 10 years.

During Pfannenstiehl’s tenure as vice chairman, the bank has tripled its asset size and has expanded its branch network from two to six branches. Pfannenstiehl also oversaw the search to hire current President and CEO, Edward Merritt.

Pfannenstiehl is the chairman/owner of Educor Inc., a post-secondary college management company. Prior to Educor, he was president and chairman of the board at Bay State College in Boston.

"We are honored to have Mr. Pfannenstiehl serve as Chairman of the Board," Merritt said. "His prior experience and business acumen will help us to continue fulfilling our mission of becoming Boston’s community bank."