A smoking boiler in the former Agassiz School caused firefighters to evacuate poll workers and voters.

The smoke forced the evacuation from about 3:45 to 4:15 p.m., said Patricia Craffey, warden of Ward 11, Precinct 9.

"We had a little bit of excitement, because it's been a boring day," she said. "We had to get out fast."

The Agassiz has been largely vacant since closing in June 2010. When boilers, which are used to heat buildings, are restarted after long periods of inactivity, they can produce smoke.

Steve MacDonald of the Boston Fire Department said it didn't take long for firefighters to search the building, find the cause of the smoke and fix the situation. He said smoke people may have seen coming from the roof of the building was not from a generator, but was venting from the boiler.

Craffey said it's not the first time in her 15 years working the polls when the school has been evacuated. About 10 years ago she remembers there was a scare in the building that prompted a similar order that everyone clear out.

There wasn't smoke in the gym, where residents of four JP precincts vote. But on exiting the building, poll worker Bonnie Booker noticed that "it smelled like burning tires."

The school serves as a voting place for Ward 11, Precincts 9 and 10; and Ward 19, Precincts 8 & 9.

There weren't many voters who had to be evacuated — the precincts reported a very slow day. As of about 5:30 p.m. the voter totals were, in order of the precincts listed above: 49, 47, about 40 and about 60.

[Editor's note: I've changed the original headline because there was smoke, but no fire. The post itself has also been updated.]