In last month’s column, I presented a “template” for a system that provides space heating, cooling and domestic water heating using a cold climate air-to-water heat pump as the primary heat source, and the sole source of chilled water for cooling. 

Looking back to 1991 when we first started searching for home designs, there was a radiant heating revival underway in the USA. 

For decades, fossil-fueled boilers have dominated the market for hydronic heat sources.

When troubleshooting a hydronic system, the piping layout is often confusing. 

Most hydronic heating systems that have renewable energy heat sources, such as solar thermal collectors, an air-to-water or geothermal heat pump or a biomass boiler also have an auxiliary heat source. 

Upfront costs and energy consumption are primary drivers when selecting a commercial HVAC system in new and retrofit projects.