Fond du Lac, Wis.-based J.F. Ahern purchased the assets of North Central Piping, a 20-year-old fire protection contracting firm in Neenah, Wis. North Central founder and President Paul Sachs will move into a project executive role with Ahern Fire Protection, a division of J.F. Ahern, for three years, at which time he will retire. Most of North Central's employees are remaining in their present positions, including the entire field crew.