This brochure outlines Dunham's product offering in 1946. It outlines how the Dunham Differential Vacuum Heating System worked. It also highlights products including Dunham differential control equipment, float and thermostatic traps, bucket traps, return traps, vacuum pumps, condensation pumps, unit heaters, convectors, fittings, pressure reducing valves, and air eliminators. There is a very good engineering section near the end of the booklet.
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...