William Thomas Chaisson, 84, died Feb. 7. peacefully at home.

After receiving his engineering degree from the University of Maine at Orono, where he was a member of the engineering honor society Tau Beta Pi, he returned to Newton, Maine, and joined his father in the family HVAC contracting business, Capitol Engineering Co.

Chaisson’s participation and contributions were instrumental to the success of many organizations. He was active in ACCA; past president of the Boston Chapter of ASHRAE; past president of Air Conditioning and Refrigeration Contractors of Boston (ARC-Boston); and a member of Sheet Metal and Air Conditioning Contractors’ National Association (SMACNA), the Association of Energy Engineers (AEE), and the American Conference of Governmental Industrial Hygienists (ACGIH). Chaisson served on many technical committees with various industry organizations over the years and was also active in his community, serving on Newton’s Design Review Committee for decades.

Chaisson maintained an active role as an engineering consultant and never considered retiring. He enjoyed spending time with his family both at home in Newton and in Wellfleet on Cape Cod.

Chaisson was predeceased by his wife of 62 years, Joan (McCarty) Chaisson; parents Clarence Chaisson and Lelia Jean (Teasdale) Chaisson; and a brother Lloyd Chaisson.

He is survived by his brother Robert Chaisson and 11 children: William, Robert, Jean, and Robert Persons; Richard and Judith Harding; Donald and Catherine; Barbara Altman; Margaret and James Gilreath; Christine and Kenneth Thompson; Deborah and Michael Boucher; John Stuart; and Thomas Daniel. He is also survived by 14 grandchildren: Madeline Mercado, Daniel Persons, Mark Persons, Melanie Gilreath Chaisson, Lelia Chaisson, Michael Altman, Anton Chaisson Boucher, Dennis Gilreath Chaisson, Clara Chaisson, Bryan Gilreath Chaisson, Henry Chaisson, Derek and Meredith Gilreath Chaisson, and Alejandra Chaisson; and three great-grandchildren: Mateo, Marcos, and Sofia Mercado.

Publication date: 3/14/2016