Prior to being mayor, Heartwell was a City Commissioner for the third ward of Grand Rapids from 1992-1999.

Heartwell currently serves as President and CEO of Pilgrim Manor Retirement Community.

Mayor Heartwell is an ordained minister for the United Church of Christ, and served for 14 years at Heartside Ministry, a program for the homeless in Grand Rapids.

He was the first Grand Rapids mayor to be term-limited out of office; during his third term in office voters approved a revision of the city charter limiting all future Grand Rapids mayors to two four-year terms.

Heartwell was the first politician to announce the death of former President Gerald R. Ford on December 26, 2006, and, along with then-President George W. Bush, then-Senator Harry Reid and then-Governor Jennifer Granholm, spoke at Ford's Grand Rapids funeral, which took place the day after Ford's Washington, D.C. funeral.