Sprinklers and an early morning dog walker squelched a fire at High Country Linen on Friday before it could do much damage.

The outcome was a happy contrast to a fire at the laundry 14 years ago: That blaze turned High Country into a pile of charred wood and hot ashes.

 In Friday’s mini-fire, a fiberglass cart filled with rags spontaneously combusted about 3:25 a.m. in one of the truck bays at the company’s North Glenwood Street facility.

Someone walking a dog heard the building’s external alarm blaring in the night and saw water running down the street. Dispatchers sent police officers to inspect the scene before paging firefighters, Fire Marshal Kathy Clay said Friday.

Within minutes of being paged, a swarm of firefighters arrived on the scene — at least 25 volunteers along with engines and support trucks.

“When you hear there’s a fire at High Country Linen, you take it pretty seriously,” Clay said.

When firefighters reached the building, there wasn’t much of a fire. A few spots were still were smoldering, but the sprinklers had doused the truck bay pretty well, Clay said.

“The sprinkler system did its job,” she said.

Mark Barron, mayor of Jackson and owner of the laundry, said workers spent Thursday collecting dirty uniforms, rags and linens from industrial customers and delivering new ones.

The rags that caught fire had been collected Thursday.

“It was a Good Samaritan,” he said of the person walking the dog. “We’re very grateful.”

The fire burned some clean towels that were waiting to be delivered, but not much else was damaged, Barron said. There was minor smoke damage, but Barron didn’t think it would be difficult to handle.

“I know a good cleaner,” he said.

The whole event was caught on High Country Linen’s camera system, Barron said. It appeared that the fire started slightly after 2 a.m., he said.

Barron received a call around 3:45 a.m. He was at the building in minutes, greeted by firefighters who were already handling the remnants of the fire.

“They were extraordinarily fast,” he said.

The business was open Friday.

The cart of rags that started the fire probably had residue from solvents and oils, Clay said. Packed into a cart, the rags generated enough heat to start the fire.

“It was the perfect mix of insulation, oxidation and air to keep the heat building,” she said.

The residue was oxidizing in the pile of rags, Clay said. It’s the same process as a nail rusting, except, in this case, the heat didn’t have anywhere to go.

When firefighters arrived, they pulled out the cart, took the rags out and drenched them. They also brought in three fans to ventilate the building.

The fire Friday was starkly different from the one that engulfed the company’s building in July 1998. That fire destroyed the company’s old building.

Fire investigators reviewed the cause of the fire for several weeks before saying that it was an accident.

When he rebuilt at the same location, Barron happily included a sprinkler system, he said.

“I knew that a sprinkler system would be key to the next building,” he said.

The system has been used only once in 14 years — Friday morning — but “it worked like a charm,” Barron said.