John Siegenthaler, P.E.

An installer uses an unpressurized thermal storage tank for drainback protection of a solar thermal system, and carefully slopes all the collectors and collector array piping for 1/4 in. per ft. drop.

Why I prefer drainback solar thermal systems.

An engineer is planning underground insulated piping for a small district heating system, which receives heat from a central boiler plant and distributes it to three separate buildings. He is planning what he calls a “primary/secondary” piping system.

Myths and methods for protecting boilers against flue gas condensation.

A significant temperature change is needed for effective thermal storage.

Every elegant hydronic piping assembly deserves an equally elegant control system. 

The piping strapped to the bottom of the floor joists is supposedly part of a primary loop.

An installer is asked to use a pellet-fired boiler to supply heat to two zones of low-temperature radiant floor panels. The system includes a three-way motorized mixing valve to reduce the supply water temperature to the distribution circuits.