Work crews have repaired the problems and all systems are back on line.
"We lost our ability to generate steam. Steam is needed to heat our buildings and provide hot water and it's also need for other systems like sterilization," said Bill Burton, UIC Spokesperson.
Earlier, UIC was redirecting patients, but none had been relocated.
Elective surgeries were cancelled, but ABC7 Chicago is told emergency room procedures can be done.
Rush University Medical Center also uses steam from the UIC plant. So, officials there were trying to cope with the situation, as well.
"We have put in to place a lot of plans to mitigate and keep our patients and visitors comfortable throughout this. And of course, [we're] making some contingency plans in case the worst should happen," said Jane Llewellyn of Rush University medical center.
"It's a problem with our facility's electrical equipment that has made it impossible for us to generate steam. So, we're attempting to fix that problem, and we're also making arrangements to bring in emergency generators," said UIC Medical Center spokesman Bill Burton.
The emergency generators were in use Friday evening, in addition to portable heaters.
Hospital staff members were also keeping doors closed to try to keep the heat in.
Interestingly, Rush University Medical Center is in the process of building its own steam plant, but it won't be done for another year.