Here is a patent issued to O.G. Johnson for the Dunham Return Trap from April 2, 1922. Thanks to Gerry Gill for finding and sharing this patent with us.
Heating Museum Help Topics
Take a stroll through HVAC history in our Heating Museum. This section of our website preserves history and answers that so-important question: What the heck is that thing? Whenever you run across anything unusual, chances are you’ll find the old literature about it right here.
Heating Museum Categories
Recent Articles in Heating Museum
This document outlines the Dunham Differential System for heating. Thanks to Frank "Steamhead" Wilsey for finding, scanning and sharing this rare information with us.
This brochure outlines Dunham's product offering in 1946. It outlines how the Dunham Differential Vacuum Heating System worked. It also highlights products including Dunh...
Here is a circa-1945 Handbook from the Dunham Heating Service. Thanks to Glen Aspen for scanning this very useful resource.
Here's a link to a PDF of the Second Edition of the Dunham Handbook. Special thanks to Colin Rush, who found it and shared the news with us. There's no date on this one b...
Here's an interesting patent from 1917 for E.H. Murphy's steam valve and fitting for heating systems. Thanks to Gerry Gill for finding and sharing it with us.
Here are patents for the components to E.C. Wiley's vapor heating system from 1916. Thanks to Steve Pajek and Gerry Gill for sharing these patents with us.
Thanks to Frank "Steamhead" Wilsey for finding and sharing these pages from Heating By Steam and Water: A Practical Treatise on House Heating, published in 1907. He tells...
This booklet contains Gorton & Lidgerwood Co.'s complete heating system product offering in 1926. It has sections on the Gorton Single Pipe Vapor Heating System, the Gort...
Here is a circa 1908 patent for one of Joseph Gorton's early ideas, his radiator appliance or valve. Thanks to Steve Pajek for finding and sharing this heating equipment ...