McAlear Vacuum Air-line Heating System
The McAlear Vacuum Air-line Heating System was one of the early vacuum steam heating systems. See their catalog here.
Systems Help Center
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
Building Technology Heritage Library
The Building Technology Heritage Library (BTHL) is primarily a collection of American and Canadian, pre-1964 architectural trade catalogs, house plan books and technical ...
We Hire the Unhirable
So we've been telling each other for years that not many young people are coming into this fascinating industry of ours. When I was still doing seminars I would ask for a...
What is a Thermostatic Radiator Valve?
You can place a thermostatic radiator valve, or TRV, on a radiator within a hot-water or steam heating system. A thermostatic radiator valve enables you to control the te...
My Partner, My Spouse
Having been married to The Lovely Marianne for more than 45 years, and having been in business with her since 1989, I feel qualified to give you this advice on how to be ...
Holohan's Lost Art of Steam Heating Seminar Video
Dan Holohan presents his Lost Art of Steam Heating seminar to The General Society of Mechanics and Tradesmen of the City of New York.
Boiler Replacement: Always Question the Existing Piping
Here’s a war story for you. I stood with a guy in the basement of a small commercial building on Long Island a few winters back. Several weeks earlier he’d attached a bra...
A New Yorker in The New Yorker
This article from the On The Town section of The New Yorker is such a nice way to end my speaking career. Many thanks to the very talented Zora O'Neill for writing the pi...
A New Look At Vacuum Heating
So let's say you're in one of America's older cities and scratching your head over an antique building that has a very confused steam-heating system. What to do? Of cours...
How Do You Paint Cast-Iron Baseboard Radiators?
This past summer, we had Burnham BASE-RAY cast-iron baseboard radiators installed in our home. One of the benefits of BASE-RAY baseboards is that you can paint them to co...