More than 20 people were hospitalized after they were sickened at a Midtown church Tuesday by suspected carbon monoxide poisoning caused by a malfunctioning stove, FDNY officials said.

Approximately 80 people were inside St. Malachy’s The Actors’ Chapel on West 49th Street near Eighth Avenue at around 10:20 a.m. when at least 24 began feeling ill, according to an FDNY spokesperson and officials at the scene. Most of the symptoms were not serious.

“At any point they could have gotten up and walked home — they were feeling ill and just needed assurance,” said FDNY Chief Stephen Spall.

The FDNY determined there were elevated carbon monoxide readings inside the basement of the church, which were caused by the faulty appliance, Spall said.

The victims were treated at the scene and taken to area hospitals for further evaluation.