A four-foot flywheel in a rooftop dehumidifier has been identified as the cause of a series of failures that have closed the rink for the past week. According to rink building committee Chair Mark Haley, a temporary dehumidifier will be brought in Wednesday, allowing the rink to reopen while the main unit is repaired. A posting on the town website said the rink will open Thursday. The unit in question has three components, called cores, Haley said. One is a…