Articles by John Siegenthaler, P.E.

Assuming that the aquastat is operating correctly, and that essential details are all present and correctly installed, why is the system behaving this way?

Every hydronic system has one or more controllers that measure and respond to temperature.

When designing hydronic circuits, most of us focus on what’s necessary for that circuit to absorb thermal energy at a heat source, carry it along like a conveyor belt and release that energy at one or more heat emitters.

The math associated with some of our assumptions can lead to incorrect conclusions.

Keep water moving to prevent frozen pipes and other issues.

Can you identify several errors or suggest some more refined design approaches for this system?

There are advantages to using this piping configuration in hydronic systems.

An installer decides to use a buffer tank between a mod/con boiler and a highly zoned distribution system. 

Have a look at the rating tables for most finned-tube baseboard sold in North America and chances are you’ll see a footnote under the table that reads something like this: “Ratings are based on active fin length and include 15% heating effect factor.”

An installer is asked to provide a multi-zone floor heating system supplied from a single-stage non-modulating geothermal heat pump.