One of the earlier gravity-hot-water-heating devices. Water would stratify in the horizontal main, with the hottest water rising to the top of the pipe. It left the tee and flowed to the radiator though the tee's top tapping. Cooler water from that radiator entered the same tee though the side tapping. Interesting things happen when you add a circulator to a system that has these tees. Thanks to Gerry Gill for finding and sharing the patent.
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This document contains the complete illustrated instructions for installing the Hercules Steam and Hot Water Heating System, a boiler manufactured by Sears, Roebuck and C...
This document contains the manufacturer's instructions for the HB Smith Series M450L Mills Water-Tube Boiler for automatic firing with oil or gas (Steam, Vapor, or Water ...
This document contains the jacket assembly instructions for the HB Smith Series 45 Mills Boiler (circa 1979).