Flat Panels or Evacuated Tubes?
Here's another interesting thread that appeared on the Wall. Wayco Wayne asks: Where do you draw the line between the two types of solar collectors? How do you decide whi...
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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
Solar Drainback Systems
This is an interesting thread that appeared on the Wall NRT.Rob asks: What are you guys using for tanks, specifically, if you are trying to do drainback solar WITHOUT pum...
Heat Pump Basics
Q: What is a heat pump? A: A heat pump is a piece of air conditioning equipment that has the ability to provide both comfort cooling in the warm summer months as well as ...
Conversion Factors
Some useful numbers to help get you from here to there: Multiply By To Obtain Atmosphere 29.92 Inches of mercury Atmosphere 33.92 Feet of water Atmosphere 14.7 Pounds per...
Mixing Passive and Active Heaters Can Lead to Problems
Sometimes, you just have to think like air. The house had been sitting on this old Connecticut street for more than 100 years. Children, grown and long gone, had once ski...
Gravity Hot Water Heating Q&A
Q: How long has gravity hot water heating been around? A: Gravity hot-water heating began quietly in the United States between 1875 and 1885. It was a Canadian import, a ...
Antique Air Vents
Here is a chapter about air valves for heating systems from Alfred King's, Practical Heating and Ventilation, 1928.
Atmospheric Pressure or So Called "Vapor" Systems
This document about Atmospheric Pressure and Vapor Systems is from Audel's Plumber's and Steamfitter's Guide No. 3, which appeared in 1925.
Attaining Maximum Efficiency & Economy from Low-Pressure Steam Heating Systems
Walter S. Finken sold KEK, a boiler cleaner. In this treatise, he explains how dirty water leads to wet steam and plenty of system problems. Thanks to Alex Marx for scann...
Bishop & Babcock Vacuum Vapor System of Steam Circulation
This document from the Bishop & Babcock Manufacturing Company showcases their vacuum vapor system of steam circulation. Thanks to Patrick Linhardt for scanning and sharin...