Modulating-Condensing Boilers
A question asked on the Wall, "Who, in your opinion, makes the best modulating-condensing boiler?" Andrew Hagen replies: My favorites in order: 1. Viessmann Vitodens 2. T...
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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
How to Have a Boiler Replaced
"We haven't had decent heat since that heating contractor left our basement." She was about as angry as any homeowner who had ever called me. "We paid good money for that...
Considerations When Using Constant Circulation
A question asked on the Wall, "What do I need to consider with a hot-water system running on constant circulation?" Mark Eatherton replies: It has to be designed into the...
Boiler Failure After Two Years
The boilers (and there were 20 of them) were laying out there in the parking lot, not far from the boiler room door. I could see them as Joe and I drove up. “Nobody knows...
How They Make Oil Burner Nozzles
There are some things you can’t help but notice about Denmark. They have windmills, but not of the Don Quixote sort. No, these are huge, three-bladed, high-tech monsters ...
Heating in France
I was in Paris one chilly November, where I had the wonderful opportunity to explain American-heating practices (such as they are) to the folks who run most of the huge E...
Heating in Russia
My buddy, Fred, was over for a visit and the talk turned to steam. Fred works for Consolidated Edison in New York City. Con Ed provides the electricity and steam for a bi...
Wood, Solar and Other European Lessons
I first went to the big ISH fair in Frankfurt, Germany in 1991 with two buddies, and I think we three were joined by only about 17 other Americans that year. ISH was larg...
A Different Way to Pipe
I was raised by Bell & Gossett and gobbled up the writings of the late, great Gil Carlson for a lot of years. I learned about Monoflo systems and primary-secondary pumpin...
Antifreeze and Heating Systems
In response to a person on the Wall who asked, "Can I add antifreeze to my heating system?" Brad White replies: Antifreeze is commonly done but like anything else, you ha...