Crews were called to the Detroit Behavioral Institute in the 3500 block of John R at about 7 p.m., said Dave Fornell, the city's deputy fire commissioner.
The site offers residential treatment for youths struggling with mood and behavioral disorders, according to its website.
Responders learned a small fire started in a vent on a lower-level clothes dryer after accumulated lint "ignited," Fornell said.
Firefighters extinguished the blaze within minutes, and no major damage was reported, he said.
It wasn't immediately clear how many residents were on site at the time. One person was rushed to a hospital after reporting seizure-like symptoms to EMS workers, but "it does not appear that was related to the fire," Fornell said.