24 reactions | This is one of five library Heating, Ventilation and Air-Conditioning (HVAC) rooftop units being lifted onto the roof of the Watertown Free Public Library. The City is replacing units that are close to 20 years old. This is a great day for the future comfort of our library patrons and staff. The Library is our community cooling center in the summer and warming center in the winter. | City of Watertown, MA - Government | Facebook