What happened to the company known as Janitrol Aero in Columbus Ohio that made aircraft heat exchangers?

Answer 1

Janitrol Aero was a division of Midland Ross Corp which was bought out by Forstman Little Investment bankers circa 1988. The division was later combined with Grimes Aerospace in Urbana, Ohio and then, I believe, sold to Honeywell. I worked as a Project Engineer in the Valve group from 1982 to 1990, a very good place to work at the time!

Answer 2

Janitrol Aero was acquired by South Wind Corp in 1969, which later became AeroTherm Corporation. AeroTherm continued to produce aircraft heat exchangers until the early 2000s when the company ceased operations.