There is a growing interest in adding air-to-water heat pumps to existing hydronic heating systems. While I support their use, I do not recommend replacing a perfectly good cast-iron boiler that still has a long service life.

Find out about piping options for retrofitting an air-to-water heat pump into an existing hydronic system.

Hydronic-based heating and cooling systems stand ready to offer plenty of design and performance benefits. One of them is the potential for thermal storage.

One of the best things about hydronic heating is there is virtually no limit to how piping systems can be customized. One of the worst things about hydronic heating is that there is virtually no limit to how piping systems can be customized.

Last month, we began discussing the HVAC system installed at my church’s newly-constructed parsonage. In this month’s column, we’ll complete the picture.

The overall objective was to create a complete HVAC system, rather than just a heating + cooling system. The system would provide space heating, cooling, domestic hot water, and fresh air ventilation.

Although the market for solar thermal systems is a tiny fraction of what it once was, I still believe there are viable applications that could help in decarbonizing thermal energy systems.

Last month, we covered the basics of classifying switches and relays based on poles and throws. Once you learn these, it’s easy to apply switches and relays to create “hard-wired” control logic - part two.

The basics of relays and switches - part one.

Several years ago, I had the opportunity of visiting the Mostra Convegno Expocomfort show in Milan, Italy. It ranks right up there with the famous ISH show in Frankfurt, Germany, as a “bucket list” event for those who are passionate about hydronic heating and plumbing.