John Siegenthaler and Dan Holohan say hydronics will get boost from green technologies.

Dan Holohan (left) and John Siegenthaler take a break during the NAOHSM convention in May 2011 in Hershey, Pa. Photo credit: Erin Holohan Haskell


Radiant Heating Report recently interviewed two of the industry’s leading experts on radiant systems and hydronics, John Siegenthaler and Dan Holohan. During our interview, John and Dan talk about where the hydronic industry and radiant systems are heading.

RHR: Where do you see the future of radiant systems?

JS: Radiant panel heating has become more of a commodity than during the “glory days” of the ’90s and early part of this century. Still, it remains a viable option for many buildings. It’s important that heating professionals see radiant panel heating as part of the mix, rather than a one-size-fits-all solution on every job. To date, many people dismiss other hydronic options that may be better fits to a given situation simply because they assume nothing can be better than radiant floor heating.

Given the rising interest in radiant cooling, I think low-mass radiant ceilings, which are configured for both heating and cooling, will make gains against floor heating.

DH: I remember when radiant was new in the ’90s and some of the Euro-based manufacturers lent an air of mystery to it, making many contractors believe their brains were just too small to grasp all of this. That changed as more Americans moved into the day-to-day management of those companies and brought in trainers who spoke the language of the contractor. Radiant became, as John says, a commodity, and contractors learned how to size and design their own systems.

Some contractors became zealots during this time (as did I) and tried to convince others that radiant hydronics was the only way to go, and if you didn’t agree, well, you were an idiot. There were, apparently, a lot of idiots, and this superior attitude didn’t get any of us anywhere.

Time passed, and even the most thickheaded of us began to realize that along with lavishing on warm surfaces, people still had to breathe, and that indoor air quality (mold anyone?) plays a large part in human comfort, or lack thereof. So the smart contractors made radiant a part of their offering, but not the totality of it.

Toss in the Great Recession and the lack of new home construction into which radiant might fit and we have the present. As we work our way out of this slump, we’re going to have an enormous stock of housing that will have to move before new houses get built, and, by then, I think we’ll be seeing radiant as a part of that construction. But I don’t think sales will be much greater than they were before the recession. Moving forward, I’m seeing the passive house coming into its own, and radiant actually brings problems to this sort of highly insulated construction.

RHR: What did you see at this year’s ISH in Germany that caught your eye?

JS: I saw an increased display of heat pumps, both geothermal and air-to-water. And an increased use of high-efficiency circulators. Many companies were offering highly refined solid-fuel boilers, both wood- and pellet-fired. I saw lots of residential as well as commercial-scale equipment. Overall, I observed a pervasive theme of environmental responsibility as the primary reason to use the latest technology.

DH: Yes to everything John mentioned. All of this was at the previous two ISH fairs, and I also noticed while walking the streets and riding the trains for hours each day, a lot of secondary shades going up on office buildings, many of these as retrofit projects, and all designed to reduce solar gain. On my train rides, I looked for solar panels, but most of what I saw was PV and not solar thermal. There were more panels than there were two years ago, but really not that much.

I’ve been to every ISH fair since 1991 and I know the show represents the vision and hopes of the manufacturers who present their products. I also spend time in the cities and the towns, looking at the buildings and talking to the locals. They are environmentally conscious, sure, but I think they’ve come to that point kicking and screaming, and through government regulation. Unless we see such laws in the U.S. (and I sure don’t see this happening anytime soon), the European model is not going to be a mirror for the U.S. movement when it comes to more-efficient heating.

RHR: Canada recently launched a “Beautiful Heat” campaign to promote radiant and hydronic systems. Can this approach work in the United States?

DH: Maybe it’s just me, but the folks who work at the Canadian hydronic manufacturers have always seemed to be better able to come together and get along than their counterparts here, and these are basically the same companies in both countries. Probably because Canadians are more polite, eh? (With the notable exception of Vancouver hockey fans.)

In Europe, hydronic manufacturers come together under the guidance of the big pump companies,  because the pump companies work with most of the boiler manufacturers as hydraulic-design partners. Under this business arrangement, the pump people are able to act as hosts for gatherings of a number of large boiler manufacturers. At these gatherings, they share ideas, economic outlooks, and even R&D with each other, and we have nothing akin to this in the U.S.

As I think about Beautiful Heat, I’ll also check back to my earlier answer about the future of radiant. It’s not just about hydronics and radiant, and an effort to make it seem that way to the public is probably going to be a wasted effort. Hydronics is a viable and green part of the mix, sure, but it’s not the whole answer to everyone’s dreams.

Oh, and the timing also seems a bit lousy. From what I’m reading, new-home building should be dead until at least the end of 2012, and an unbelieving and/or frustrated contractor who’s thinking cheap can turn the Beautiful Heat campaign on its head with a just few negative comments to a builder or a homebuyer.

It’s a noble idea, and I adore the Canadians and their passion (eh?), but my eyebrows remain raised for now.

JS: It’s hard to tell at this point because it has just launched in Canada. Those who organized this campaign understood that taking a message directly to consumers requires major financial commitments (millions rather than thousands). They appear to be on track with these commitments. At this point, the Radiant Professionals Alliance has identified Beautiful Heat as something it would like to replicate in this country. We should know more on this in 2012.

RHR: Who will train the next generation of radiant system designers and installers?

DH: Social networks on the Internet.

JS: I don’t see a single entity emerging as the epicenter of such training. It’s likely that web-based delivery of training information will continue to expand. Hydronic heating pros need a wide variety of information dealing with mechanical, electrical, chemical and architectural technologies. It’s good for hydronic specialists to get outside of their daily bread and butter to learn about emerging trends in building science. Those who would commit to continuous learning as essential to their business will be the most successful.

RHR: How will the growth of solar thermal and geothermal systems affect hydronic product sales?

JS: Increased interest in solar, geothermal heat pump and any other thermally based renewable technology is good news for hydronics. However, the traditional hydronics industry has to learn not to think of itself as an isolated niche in the HVAC market. Rather, it should think of itself as the technology that enables all thermally based renewable heat sources to deliver on their promised performance.

Doing a good job with the hydronic details enhances any thermally based renewable energy heat source, and vice versa. The heat sources may be new, but control and delivery remains essential to overall system performance and customer satisfaction.

DH: I’m convinced the future of hydronics is commercial, and I agree with all that John has said. Hydronics will be primarily about moving and delivering Btu, regardless of the source of the heat, and that’s going to play a large part in geothermal, solar, waste heat and whatever else comes along as a source. There sure are some interesting days ahead.