Seven people were hospitalized, including two with serious injuries, after a faulty oil burner caused a severe carbon monoxide leak in the Bronx on Wednesday, according to Fire Department officials.

The leak sprang inside a Grant Ave. residential building near E. 165th St. in Concourse shortly before noon, an FDNY spokesman said.

The Fire Department recorded CO readings as high as 480 parts per million, more than 400 ppm above the Occupational Safety and Health Administration’s recommended eight-hour exposure limit of 50 ppm.

Medics rushed seven people to Jacobi Hospital, including five with non-life-threatening injuries and two in serious condition.