Articles by John Siegenthaler, P.E.

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.

Air-to-water heat pumps and water-to-water geothermal heat pumps provide warm water for space heating, domestic water heating, and chilled water for cooling. Switching a hydronic heat pump system from space heating to cooling and vice versa seasonally is relatively simple. The system operating mode is changed at the thermostat or a dedicated system mode switch with heat, off, and cool settings.

If your office routine is like mine, you probably type passwords into your devices all day to access essential websites and software. Sometimes you forget complex passwords and have to go through the hassle of resetting them. Financial websites may require monthly password updates.

I attended a conference hosted by the Building Performance Association and presented on air-to-water heat pump systems. Many professionals were interested in heat pumps, especially ductless air-to-air systems. One person mentioned the difficulty of finding qualified installers for air-to-water heat pumps and noted the higher cost compared to ductless air-to-air systems.

Biomass boilers burn various fuels and come in different designs. Water vapor is produced when burning wood-based fuels, and the resulting condensate can be acidic and corrosive to metals like carbon steel and iron.

Flow direction is crucial in hydronic systems. Most designs have a fixed flow direction, but there are situations where reversals can occur. It's important to address these proactively to ensure smooth operations.

In last month’s column, we discussed the design and actuation of 3-way diverter valves. This month, we’ll look at several applications for these valves.

Primary/secondary piping is a way to achieve hydraulic separation by connecting multiple hydronic circuits with their own circulators to prevent interference. Using a pair of closely spaced tees is a common method to achieve this.