Geo-normous problems

The Glitch:

An installer is asked to provide a multi-zone, floor heating system supplied from a single stage non-modulating geothermal heat pump. The radiant floor panels will be low thermal mass. The system also needs to provide domestic water heating. The system he designs is shown in figure 1. Assume that the earth loop is sufficient for the capacity of the heat pump. Can you identify several problems that are likely to develop if this system is installed as shown?

Are you an ace troubleshooter?

Within the pages of this magazine, PM’s Hydronics Editor John Siegenthaler, P.E., will pose a question to you, our readers, to review a system’s schematic layout and discover its faults, flaws and defects. Discover archived “The Glitch & The Fix” exercises at its radiant-focused website, www.radiantandhydronics.com. Good luck!