A wrong turn on the way home from Taco Bell changed Adam Thiel's life.

It was 24 years ago when the then-19-year-old student at American University got lost returning to campus and passed a firehouse advertising free EMT lessons.

Thiel, impressed by the emergency responders who rushed his father to the hospital when he was dying of cancer, signed up and never looked back.

"Once I got hooked, I was all in," said Thiel, Philadelphia's new fire commissioner. Thiel, 43, is the first non-Philadelphian to lead the city's fire department. He has worked in Maryland, Virginia, Arizona and North Carolina. He has been fire director for Virginia, chief of the Alexandria fire department, and deputy chief of homeland security for Virginia.

Despite a standout resume, his appointment was not universally applauded here.

Club Valiants, Philadelphia's association of black firefighters, said it was disappointed that the acting commissioner, Derrick Sawyer, an African American, had not been kept on in the executive position.

"Although Fire Commissioner Thiel has an extensive background, he has some huge shoes to fill," president Lisa C. Forrest said in a statement. "It will take a collaborative effort from the stakeholders to continually move this department in a progressive manner."

The firefighters' union, Local 22 of the International Association of Firefighters, said it would have preferred an internal selection.

Despite that, Thiel said his first two weeks have been welcoming.

"The one thing about public safety, in general, we are kind of a big family so I really do feel like this is my family now," he said, in an interview in his office at Second and Spring Garden Streets last week.

Thiel, who makes $180,000 a year, has inherited a department of 1,790 with slowing response times and funding challenges. It is still reeling from the death in 2014 of Joyce Craig, the department's first female firefighter to die in the line of duty.

Last year, the department was tainted by a sex scandal in which two battalion chiefs, a captain, a lieutenant, a paramedic, and two firefighters faced discipline for sexual encounters with a paramedic.

Racial tensions too have long bubbled below the surface.

When Thiel, who is white, started as chief in Alexandria in 2007, he walked into a similarly skeptical and somewhat racially divided department of 250 members, said John Morehead, who led the local chapter of black firefighters there.

"Some of the same feelings probably going on in Philadelphia were going on here," Morehead said. "We didn't traditionally trust the structure to select somebody to do the right thing."

But Thiel surprised him, Morehead said.

Thiel appointed a diverse executive staff, attended community events that the black union held and made training more inclusive.

The first class of firefighters hired under Thiel better represented the community, Morehead said.

Thiel also tackled a vicious anonymous blog with hateful posts about people in the department. "He ended the bullying. He said, 'I will find you and I will grind you out,' " Morehead said, "And that blog disappeared fast."

Andrew Snead, Thiel's second in command in Alexandria, said the tension when Thiel took over "was unbelievable."

"It was black against white. It was old against new. Everybody had established a corner," he said.

Snead, who is black, said Thiel, got people to start working together.

Thiel, at the moment, is in the process of meeting with Club Valiants, Local 22, and the National Association of Hispanic Firefighters.

"I don't know a fire department that doesn't have these problems," Thiel said. "I think we really do need to establish dialogue, bring people together. You just can't avoid the fact that a successful organization is one that's diverse and inclusive."

Snead described Thiel as someone who can "play and coach."

He recalled a residential fire in 2011 when a steady rain quickly turned to flash flooding.

"Our unit was trapped, all of the sudden waist high in water," Snead said. Thiel instructed the unit to tether together so a second team could pull them from the rushing water.

"His coordination, calmness and coolness, I know it saved lives," Snead said.

Thiel grew up in Chicago, and earned a degree in history at the University of North Carolina at Chapel Hill, after transferring from American. He went on to obtain a master's degree and complete coursework for a Ph.D., but didn't finish his dissertation.

He worked for two fire stations serving Durham, N.C., then for the Fairfax County Fire & Rescue Department in Virginia before becoming Virginia state fire director. He did a three-year stint as deputy chief of the Goodyear, Ariz., fire department, and then spent seven years as chief of Alexandria's fire department. Most recently, he was deputy secretary of homeland security in Virginia.

Thiel is trained in scuba rescue, competes in triathlons, and likes the fitness regime CrossFit. He is divorced with two children, 12 and 14, who live in North Carolina.

He comes on board as Philadelphia completes its review of Craig's death.

He would not discuss the findings until the full report is released but said the report will offer a road map for change.

Thiel said he's impressed so far with the department especially given Philadelphia's landscape and thin resources compared to other urban departments.

"There aren't many places you can go where you have buildings 200-plus years-old next to tower cranes building the absolute latest, most modern, high rises," Thiel said. "So we need to be able to calibrate our resources to that unique environment."

Thiel, who lives in Roxborough, said he has long admired the history of the city and its fire department. He recalled how after he was named the new commissioner, he received a call from Harold B. Hairston, who had been the city's first black fire commissioner.

"This is such a dynamic, iconic city and it's a great fire department," Thiel said. "When I was coming up, Commissioner Hairston was one of the greats, a legend in our business. The opportunity to be part of that, it's a little surreal."