John Siegenthaler, P.E.

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.

There are many scenarios in which flow at some location within a hydronic system has to be directed along one of two possible flow paths. When a single valve is used to create this routing, it’s called a diverter valve. In part 1, we're digging into motorized 3-way diverter valves and actuator options.

In rural upstate New York, residents harvest trees for firewood using chainsaws and hydraulic splitters. I burn about two face cords annually in my wood stove, enjoying its warmth during winter and relying on it during power outages caused by outdated utility lines.

Last month, we discussed how solid thermal energy storage, combined with an air-to-water heat pump and an electric boiler, provides a platform to leverage time-of-use electrical rates in ways that can benefit customers as well as the utility providing the electricity.