Profile: Charleston, Inc. specializes in heating, ventilation and air conditioning controls, control systems, equipment and supplies. Our product line includes hydronic expansion & air elimination tanks, sheet metal hangers, pipes & fittings, heating & air conditioning systems, electric boilers, and saw blades & tools. We provide many types of stub-out options, ranging from traditional copper plated stub-out bars to galvanized brackets with plastic inserts. Our RA-32 is the high-end residential model for whole house water heating. It is used in demanding applications where incoming water temperatures or total flow requirements dictate more power than the RA-28.