Articles by John Siegenthaler, P.E.

Last month, we started with an air-to-water heat pump for space heating and added an auxiliary heat source and chilled water cooling. This month, we’re adding domestic water heating, similar to last month’s setup.

Air-to-water heat pumps, especially for larger systems, can be used in stages for efficient temperature control and flexibility, utilizing variable-speed compressors and specific piping setups to manage heating and cooling loads.

A review of a flawed hydronic heating system uncovers critical errors, such as improper circulator placement and restrictive mixing valves, leading to uneven warmth and corrosion issues. This underscores the need for proper design and installation in hydronic systems.

Hydronically-heated concrete floor slabs offer comfort but can be slow to warm up. A proposed solution uses a heat pump and variable-speed circulators to provide rapid heating through air handlers, ensuring quick warmth during cool days while maintaining energy efficiency.

As government electrification target dates loom in the near future, and power transmission systems get pushed closer to their limits, utility companies continue implementing ways to manage peak demand.

In 1986, I installed a 1.5-ton geothermal heat pump in my home using two 500-foot horizontal HDPE earth loops. After digging a trench, I connected the loops to the pump and opted for a 2 HP swimming pool pump to fill and flush the system, as a garden hose couldn't provide the needed flow rate.

A project needs medium- and low-temperature radiant floor panels. The installer proposes using a mod/con boiler with a 1-inch tempering valve for lower temperatures and plans to pipe the entire system with 1-inch tubing. What potential issues could arise from this design?

Thermal storage enhances the efficiency of renewable energy heating systems, like pellet-fired boilers and solar collectors, by storing low-cost, off-peak electrical energy for future use. It's vital for reducing energy costs and ensuring consistent heating, with auxiliary boilers providing backup when needed.

In 2024, the North American air-to-water heat pump market saw significant expansion, with nine new offerings introduced at the January AHR show by companies new to this category. By year's end, at least 18 companies either have or plan to offer these pumps in the U.S. Read the list of these companies as of mid-2024.

Geothermal systems use HDPE tubing for closed-loop earth heat exchangers, buried several feet below the surface.