The Big Fault in One-Pipe Heating
In 1935, John W. Schulz, writing in Fuel Oil Journal, makes a brilliant case for looking more closely at steam systems designed with coal in mind when the time comes to s...
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Our comprehensive HVAC Systems Help Center covers a wide range of HVAC-related topics, including air conditioning and heat pumps, geothermal, hot-water heating, thermostats and controls, solar, steam heating, and warm air. We also have a section of informative and entertaining articles to help you sharpen your HVAC business skills. And our Heating Museum is a captivating journey through the evolution of HVAC technologies.
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Recent Articles
The Dunham Air-Line Service Valve and Its Application
This circa-1916 bulletin from C.A. Dunham Co. describes Dunham's heating product offering for a system to compete with Andrew Paul's heating system.
The Dunham Blast Trap and Its Application
This bulletin from C.A. Dunham Co. is from 1916 and features the Dunham Blast Trap and Its Application.
The Dunham Packless Inlet Valve
Packless radiator supply valves kept air from working its way into a vacuum system. This bulletin from C.A. Dunham Co.
The Dunham Reducing Pressure Valve and Vacuum Pump Governor
This bulletin from C.A. Dunham Co. is from 1916 and features the Dunham Reducing Pressure Valve and Vacuum Pump Governor.
The Dunham Vapor System
This circa-1916 bulletin contains helpful information about the Dunham Vapor Heating System. Thanks to David Cordes for sharing.
The Dunham Victory Line
The Dunham Victory line appeared in 1943 and had to meet Government specifications since we were at war. Note how the Vari-Vac system was then called the Dunham Coordinat...
The Hartford Water Line Return Connection
This is a very clear explanation of the Hartford Loop. It's from the Western Plumbing and Heating Journal and it appeared in April, 1943.
The Heating Plant by H.W. Means
Thanks to John Van Hoesen for finding and sharing this interesting article about how to fire a steam boiler in an elementary school, circa 1916. It urges the fireman to k...
The Hoffman - A Venting Valve for Every Service
The Hoffman - A Venting Valve for Every Service shares the Hoffman story, as told 30 years after George D. Hoffman introduced his first vent. Wonderfully clear language h...