John Siegenthaler: Simple and effective
Most hydronic heating systems that have renewable energy heat sources, such as solar thermal collectors, an air-to-water or geothermal heat pump or a biomass boiler also have an auxiliary heat source.
View ArticleJohn Siegenthaler: One source does it all
For decades, fossil-fueled boilers have dominated the market for hydronic heat sources.
View ArticleJohn Siegenthaler: It makes a difference
In last month’s column, I presented a “template” for a system that provides space heating, cooling and domestic water heating using a cold climate air-to-water heat pump as the primary heat source, and...
View ArticleJohn Siegenthaler: An internal matter
The classic way of estimating heating load in smaller, envelope-dominated buildings is to assume the rate of heat loss is proportional to the difference between the inside and outside temperature.
View ArticleJohn Siegenthaler: The anatomy of a municipal pellet boiler system
I’m sure everyone reading this column has heard the adage “a picture is worth a thousand words.”
View ArticleJohn Siegenthaler: Good intentions
I don’t know about you, but after more than 40 years of working in the HVAC industry I find myself a bit overwhelmed trying to keep up with standards, codes and other well-intentioned regulations,...
View ArticleJohn Siegenthaler: Whittling away at watts
When designing hydronic circuits, most of us focus on what’s necessary for that circuit to absorb thermal energy at a heat source, carry it along like a conveyor belt and release that energy at one or...
View ArticleJohn Siegenthaler: An open and closed case
In the closing days of 2020, the federal government approved one of the largest renewable energy spending bills in over a decade.
View ArticleJohn Siegenthaler: Boosting Biomass Btu
Last month, we discussed using a non-pressurized thermal storage tank, in combination with brazed plate heat exchangers in a system supplied by a cordwood gasification boiler.
View ArticleJohn Siegenthaler: Respecting the Laws — of thermodynamics
One of the most fundamental principles used in all areas of science and engineering is the first law of thermodynamics.
View ArticleJohn Siegenthaler: “Solar DWH+” systems
It’s been a while since this column addressed solar thermal applications.
View ArticleJohn Siegenthaler: Piping options for multiple thermal storage tanks
Nearly all systems using cordwood gasification or pellet-fueled boilers perform best when the system includes a thermal storage tank.
View ArticlePart 2: Piping options for multiple thermal storage tanks
Last month, we looked at ways to connect two or more thermal storage tanks into an array with sufficient volume to meet the needs of a biomass boiler — or other thermal storage requirement.
View ArticleCold on the right; hot on the left
“Cold on the right; hot on the left” is a jab that is not particularly endearing to plumbing engineers. If it were ever uttered, it’s usually in the context that the task at hand is very easy.
View ArticlePellet boiler meets modern hydronics
Over the last several years, I’ve been reviewing submittals for proposed heating systems using pellet-fired boilers. The submittals come from heating professionals ranging from contractors to...
View ArticleJohn Siegenthaler: Part 2: Pellet boiler meets modern hydronics
Last month, we looked at a piping approach for adding a pellet boiler and panel radiators to an existing two-zone baseboard system. The system’s original oil-fired boiler was being retained as an...
View ArticleJohn Siegenthaler: Paying for heat
Apartment buildings and condominiums are home to families with different comfort preferences or attitudes on energy use. Similarly, many commercial buildings are divided into spaces where tenants have...
View ArticleJohn Siegenthaler: Radiators for renewables
Modern panel radiators are one of my favorite hydronic heat emitters. They’re easy to install, emit radiant and convective heat, and have high-quality powder coat finishes.
View ArticleJohn Siegenthaler: What you don't pay for
Heat pumps move heat from low-temperature sources to higher temperature loads. There are many types of heat pumps, but they all perform this basic thermodynamic mission.
View ArticleJohn Siegenthaler: Peaking ahead
As interest and incentives build to transition space heating and domestic water heating systems away from fossil fuels and toward electricity, a somewhat predictable but only marginally quantified...
View Article