The 20,000-square-foot east Stockton building that once housed Rod Johnson's Air Conditioning burned to the ground early Tuesday morning in a fire of unknown cause, according to the Stockton Fire Department.

"We've got a whole bunch of customers, and we've got vehicles and some loyal employees, so everything's not that bad. A little bump in the road," Johnson said.

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Employees of the more than 50-year-old company are working in a temporary location until he is able to locate another property, he hopes, near Highway 99.

 "We're going to get bigger and better ... it's inspiring me to be better," he said.

Stockton Fire received a call about the fire about 2 a.m. Tuesday and 39 firefighters, eight engines and three trucks responded to the massive fire at 1553 North Broadway Avenue, said Battalion Chief Brandon Doolan. The cause is still under investigation, he said.

Several columns and mounds of warped sheet metal were all that remained of the building Thursday morning. Johnson said there were no employees at the shop when the fire broke out, and said he did not know what might have caused it.

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Johnson's business is a household name in Stockton.

"I've always said that I'd be loyal to my customers ... We're not going to abandon them," he said, adding that Johnson's has 20,000 customers.

Johnson's business has also donated hundreds of turkeys to the Emergency Food Bank of Stockton/San Joaquin and hosted the Mary Graham Children’s Foundation Charity Golf Tournament at Oakmoore Golf Course in 2015.

Tuesday's blaze was not the first time fires have started in the industrial neighborhood around Rod Johnson's business, off of Highway 99. In March, bins stored behind a business two properties up the road from Johnson's, caught fire, Doolan said.

A few years ago, another fire razed part of a building behind Johnson's shop and caused the roof to collapse, he said.

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Record reporter Aaron Leathley covers business, housing, and land use. She can be reached at aleathley@recordnet.com or on Twitter @LeathleyAaron. Support local news, subscribe to The Stockton Record at https://www.recordnet.com/subscribenow.