By using a pot of mercury and a submerged pipe, this device separated the water in the system from the water in the expansion tank. Honeywell called it the Heat Generator and it allowed open hot water systems to operate under pressure, and at higher temperatures, but still remain safe. This was a major advance in hot-water heating in that it allowed the hot-water people to compete with the steam people, whose prices were usually less. The patent dates to October 22, 1907. Thanks to Gerry Gill for sharing this with us.
The Improved Webster Type "R" System of Steam Heating is a service bulletin from Warren Webster and Company (The Pioneers of Vacuum Steam Heating), established in 1888.
This manual was created by O-E Specialty Manufacturing Co. and outlines how to install the "O-E" Perfect System, which is a Vapor Vacuum heating system.
Here is the original Installation and Operating Instructions and Parts List for The H.B. Smith Company's Oil Fired Cast Iron Hot Water Boilers (No. OHB-13W). This is esti...