Systems Help Center

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 ...

This circa-1936 patent is for the Hoffman Specialty Company's boiler return trap for heating systems. Thanks to Gerry Gill for finding this patent, and for sharing it wit...

Here is the Hoffman Data Book for Heating Engineers and Contractors, Second Edition compiled for the Hoffman Specialty Company in 1925. "The Hoffman devices which transfo...

Here are patents from 1922 for the Hoffman Specialty Company for their vapor heating system with differential loops. Thanks to Steve Pajek for finding and sharing these.