The problem was fixed by Monday afternoon, but by then some students had already faced two freezing nights.
Several students in other residence halls also called the Department of Housing and Residential Education with complaints about individual rooms.
The individual problems -- most of which were related to cold air in heating pipes -- were quickly resolved, said Christopher Payne, director of the Department of Housing and Residential Education.
The only residence hall-wide heating problem was in Alderman, Payne said.
Maintenance staff began troubleshooting the problem when they were made aware of it late Saturday night, and Alderman residents were informed via e-mail about their progress.
While waiting for the heat to return, Alderman residents had various ways of coping. "I was sitting in my room with a winter coat and gloves on," said sophomore Catherine Cheng. "It was so cold I was dreading to take a shower because I thought I would get hypothermia."
Other residents sought refuge from the cold by fleeing to other residence halls. "I've got some friends on South Campus, and it was unbearable, so I went and stayed with them," said junior Latorya Jarman. "My fish froze. It was dead. The first living thing I ever owned by myself, and it died. It was so sad."
Curtis Wilson, the maintenance supervisor for Mid and North Campus, said he had space heaters ready in case Alderman was not warm by Monday night.
But maintenance workers identified a problem with the building's heat pump Monday and fixed it Monday afternoon, said mechanic William Howard.
Once the problem was fixed, it took a few hours for the building to heat up.
"Any time it's this cold for two or three days, it's going to take a while for it to heat up," said Wilson, who noted that the heating system has underground iron pipes, which take a long time to get warm.
Maintenance worker Rick Mangum said the 50-year-old hot water heating system is being replaced with a more efficient forced-air heating system.
"(This will be) much more efficient and save a lot of money," Mangum said.
Payne said any students with heating problems should fill out a facility maintenance request, which can be found via a link from http://housing.unc.edu, the housing department's Web site.
For students' information, Howard said the unlabeled knobs on residence hall radiators affect heat flow by opening and closing a valve. "Clockwise is off -- counterclockwise is open," he said.
Mangum said staff worked hard to correct the heating problem. "The student is our customer, and we plan to serve the student efficiently," he said. "Rain or snow or sleet or hail, just like the postman."
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