Articles by John Siegenthaler, P.E.

These are common design pitfalls that may seem effective as they are. Review them and identify changes that could enhance the layout.

Millinocket is near utility-scale wind turbine farms where strong winter winds can lead to over-generation of electricity, surpassing local grid demand. While it might seem intuitive to shut down some generation equipment during such times, the process is not as simple as flipping a switch.

Some hydronic heating systems use slab-on-grade floor heating combined with an air handler or fan-coils in other areas of a building. This approach is also used for heated basement floors combined with a “hydro-air” delivery system for the main living areas.

Zoning has always been a premier benefit of hydronic heating and cooling systems. There are many zoning configurations capable of delivering heat (or cooling effect) when and where it’s needed in a building, with minimal effect on the temperature in other parts of the building. Some methods use circulators to create flow in each zone; others use either motorized or thermostatic valves to regulate flow.

One concept that’s getting increasing attention among HVAC engineers is “resilient design.” It refers to approaches that - ideally - allow systems to remain operational under very abnormal conditions, or minimize effects that could cause major damage to systems when and if they are otherwise rendered inoperative.

While I admit to not being fully informed on the latest things from Google, Apple, Chat GPT, or social media, I’m confident that I can still pass along advice to those who are new to the hydronic industry, especially those involved with designing systems

A building with slab-on-grade heating from a cast iron boiler plans to expand. A monobloc air-to-water heat pump will provide heating and cooling for the new space via a fan-coil unit, with the existing boiler serving as backup.

Air-to-water heat pumps are gaining popularity in North American hydronic systems, but many practitioners are discovering that they operate differently from boilers.

What happens if there’s a simultaneous call for domestic water heating and cooling?

Fortunately, our industry is at a point where the question "But what do I do about cooling?" can be answered, with confidence, and by the same hydronics professional offering heating.