Jameson Elementary School in Old Orchard Beach was briefly evacuated Wednesday when a malfunctioning heat pump sent smoke billowing into the cafeteria as staff ate lunch.

No students were in the building at the time because of a prescheduled professional development day, said Regional School Unit 23 Superintendent John Suttie. No one was injured, he said.

The smoke appeared around 12:45 p.m. and teachers nearby pulled the fire alarm. Firefighters from Old Orchard beach and surrounding towns responded and discovered that the electric motor in the heat pump had overheated, producing the smoke, Suttie said.

There were no flames, and damage to the building was minor, he said. A contractor was on site Wednesday afternoon to fix the equipment. The cost of the damage was not immediately clear, Suttie said.

“There is some sheet rock and flooring that is damaged,” Suttie said. “The blessing here in disguise is we had no kids.”

Suttie said parents should plan for in-person classes Thursday. If problems arise, the district will notify families to make other arrangements.