After the plaintiffs took occupancy, they encountered considerable problems, among them, vermin infestation, leaking ceilings, porous walls, and lack of heat. In the winter, the heat problem required the plaintiffs to close off two bedrooms and sleep in the living room with their children. The plaintiffs complained about these conditions to the defendant. When he made no repairs, the plaintiffs complained to the Department, which issued notices calling for immediate correction of the conditions, especially the lack of heat. During that period, the defendant was served by the Department with four additional notices and orders. In October, 1984, the plaintiffs began withholding their rent, and on January 10, 1985, they commenced this action in the Housing Court. The heating problem was remedied shortly thereafter when the defendant was served with a notice to appear in the Housing Court to show cause why an injunction should not enter ordering him to provide facilities capable of heating each room in the apartment. All in all, more than a year elapsed after the Department served the defendant before he corrected the lack of heat and complied with the Department’s orders to correct other serious violations.