This circa-1940 patent is for McDonnell & Miller's 101-A Automatic Feeder. Thanks to Gerry Gill for finding and sharing this patent.
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Recent Articles
MEPCO Steam Traps were widely used on the Dunham-Bush Vari-Vac system. Thanks to Brad White for sharing this information with us.
Here is some very good literature on the Milwaukee Valve Company's vapor heating product offering from 1935, including the MILVACO Air Line Valve, the Type "M" Boiler Ret...
The Moline System of Heating was a famous vapor heating system, named for the Illinois city. There is no date on this booklet, but it is probably from around 1915. Specia...
The Mouat Vapor System was one of the classics of vapor heating! Here is an excerpt from The Heating and Ventilating Magazine explaining how this system works. And you'll...
Here is the patent for an interesting piping system, offered by the Murrays, father and son. Gerry Gill, who found and shares this with us, comments, "This patent lists b...
This article is from Combustion magazine in January 1930. These boilers heated many a New Yorker.
Here's a playful article from The Craftsman magazine (May 1914), published during a time when vapor/vacuum heating was just coming into its own. One of the huge advantage...
The Norwall Manufacturing Company made a variety of products for vacuum steam heating systems. This document about their automatic air valves is from 1906.
The Nuvacuumette Vapor Heating System was developed in England around 1905. This simple vapor system circulated steam at temperatures between 180-200 degrees F, while doi...