A malfunctioning exhaust fan left most of the 250 buildings on campus without heat or hot water for about seven hours Dec. 14. Black smoke billowed out the windows of the Central Heating Plant, and some mechanical and electrical cables were damaged, all caused by the breakdown.

Campus activities were unaffected, thanks in part to the warm temperatures that day, said Ed Wilson, the plant's manager. Three employees were in the plant at the time. None were injured.

The problems began sometime in the early morning, when an induced draft fan on a boiler stopped working, which caused combustion gases from the boiler to back up into the facility. "It was as if at home you had the boiler or fireplace running and someone plugged up the smokestack," Wilson said. "The smoke and some fire backed up into the facility." Normally the fan funnels exhaust through a particulate remover and out one of the plant's smokestacks.

Ithaca Fire Department responded to a call at about 9 a.m. A team contained the fire and monitored carbon monoxide levels until it was safe for employees to re-enter the building. The department left the scene at about 11 a.m.

The university sent out an e-mail alert at about 12:30 p.m., saying that the plant has stopped exporting steam to campus. The message asked the campus community to conserve heat by closing windows and minimizing the use of hot water. Workers at the plant started several of the other boilers in the early afternoon, Wilson said, with full service restored by 6 p.m.

"I am very appreciative that no one was hurt, of the speed and efficiency of the Ithaca Fire Department and the dedication of so many employees who worked overtime to get the system back on line," said Stephen Golding, executive vice president for finance and administration.

The cause of the malfunction is being investigated, but Wilson suspects that the fan was either vibrating too much or the vibration monitoring equipment failed. The malfunctioning boiler, one of the plant's six boilers, will be out of service for several weeks for assessment and repair.

The boiler has a history of high reliability but has malfunctioned for various reasons several times before, the most recent being three years ago. "We've taken some mitigating steps to try to prevent this type of thing," Wilson said. "We'll take a really good look at its operation and have the manufacturer look at it, and find out exactly why this happened." The boiler will not pose a problem during winter break, he said. "Campus is not at risk."