Subscribe to our newsletters & stay updated
Hydronics isn’t as popular as forced-air. If there was a scoreboard for the game of hydronics vs. forced-air systems, the air-based team would be resting their starters. Will hydronics break out of a niche in the North American market? Are we lost in the nostalgia of interesting hydronic systems that are a misguided business model? As an industry, where do we go from here?
Hydronics is the best way to heat and cool a building. For qualitative reasons, people generally like most of the following attributes of hydronic systems: quiet operation, less dust blowing around, low-maintenance operation, excellent energy efficiency potential, ease of zoning, architectural flexibility, operative temperature control and general comfort*. (*Comfort is not an easy thing to define, but the human body is influenced by radiation from the surrounding surfaces; being able to control the temperature of the surfaces gives you active control of something forced-air can’t change.)
From a quantitative perspective, the engineering math is on the side of hydronics! The specific heat capacity of water is higher than air, by a lot. It is fundamentally smarter to move energy with a unit of a liquid than it is with a unit of air. How many air-cooled nuclear power plant reactor cores have you seen? Not many because liquid is the best way to move energy. The specific heat capacity of water is 1.2 Btu/lb at 140 F. For air, at the same temperature, the number is 0.24 Btu/lb.
If you are reading this magazine, you have probably heard some version of these arguments many times before. These arguments are not good enough to steal market share from forced-air companies. I wish they were, but our industry may need to take a different approach to stay relevant.
Here is where I’m going to put my hydronics bull horn down for a second. We need forced-air systems. That is a borderline traitorous statement in the hydronics community. I grew up in a home where almost everything was heated by water. Including, but not limited to: a chandelier, a bed frame, a dog-shaped concrete lawn ornament, a copper harp, a cat house, ceilings, walls and floors. I have hydronics in my blood, but I can also acknowledge that it isn’t everything for everyone.
For years, I thought the challenge was for hydronics to prove forced-air to be an inferior technology that should be vanquished like asbestos insulation. While I still think hydronics is the best-in-category system in most measurable criteria, I have come to terms with the reality of modern construction. If you built a warehouse to 1970s construction standards, maybe you would have enough fresh air infiltration to keep the indoor air quality at an acceptable level without some mechanical ventilation. As building codes become more energy efficient, you can’t rely on infiltration and a leaky envelope for air changes. We need to tumble some air to keep buildings healthy, and hydronics alone can’t do it. Hybrid (combined hydronics and forced-air systems) is the best basis for design.
In a perfect world, water-based systems would be designed to handle most of the sensible load in a building. An HRV, ERV or DOAS system would be sized for latent loads and indoor air quality-boosting air changes. Hydronics is great at heating and cooling buildings; forced-air is great at keeping your new house from smelling like an old locker room.
Currently, from a market share standpoint, hydronics is closer to Motorola numbers than it is to Apple or Samsung, to use a cellphone analogy. We aren’t a big player in regions where people don’t plan on living their entire lives in one home. In the U.S., if you don’t like a certain attribute of your home, you change shells like a hermit crab.
The National Association of Realtors keeps track of median tenure of a family in a home in the U.S. From 1985 to 2008, the average was six years. As of 2016, the average is now 10 years. Why is that the case? “The fall in home prices during the housing crisis left many homeowners in a negative equity situation (where their home was worth less than the mortgage on the property). Also, the uncertainty of the economy made some homeowners much more fiscally conservative about making a move.”
Outside mortgage related topics, the North American market doesn’t value energy efficiency the same as hydronics-dominant markets, like a lot of European countries. If our energy prices quadrupled on this continent, energy efficiency would jump higher up the list of priorities for homeowners. Right now, the heating system ranks well below cosmetic options like fancy countertops and appliances. Europeans also spend generations in the same homes more frequently than North Americans.
Hydronics companies tend to be very technical in their approach to the world, as seen in my specific heat paragraph earlier. Forced-air companies tend to be excellent at building brand recognition with the non-technical population. If hydronics manufacturers, wholesalers and installers all put their money together and sat down at a poker table with the big names in forced-air, we wouldn’t meet the table minimum for a single bet. It is rare for any single brand in a hydronics system to be recognized by the average homeowner, while Carrier is written on the side of a 49,250 capacity arena in Syracuse, New York, as a single example.
According to Opensecrets.org, a lobbyist tracking database, Carrier Corporation’s parent company United Technologies lobbied the U.S. government to the tune of over $9 million dollars in 2016. They spent over $11 million lobbying dollars in 2017. In a parallel universe where hydronics has a Carrier marketing and lobbying budget, maybe our market share would be different, because our political system rewards lobbying.
Why don’t we all quit our hydronics jobs and go work for forced-air mega corporations? We are justified in loving hydronics for the elegant environment it creates in buildings, where the average U.S. citizen spends 90 percent of their time. Hydronics can be energy efficient, silent and comfortable at the same time, which is a set of criteria that is hard to match.
On a long enough timeline, hydronics has a path out of niche technology. It just may take a spike in energy prices before the upfront cost differential becomes a no-brainer business decision for any new construction project. Hydronics could also springboard if the median tenure of a family in a home in the U.S. jumps up another five or ten years.
For the time being, there is nothing wrong with hydronics being a niche industry. If you were a car dealer, would you rather sell a few Cadillacs or 50 Chevy compact cars? Lower volume, higher quality-heating systems put me through college (thanks Mom, Dad and hydronics).
My point is, we aren’t going to win market share from the forced-air giants by throwing punches at them; forced-air is going to be part of future buildings. The best available system on the market is a radiant system, assisted by forced-air for the latent load. We should fight with the tin benders, not against them to improve the delivered heating and cooling system to the homeowner. To some extent, our short-term relevance in the hydronics industry may depend on how well we can adapt to hybrid water/air systems.
Loving hydronics isn’t misguided nostalgia; it is a long play for the nerds like me who are stubborn enough to hold on until there’s a clearer path to get our systems to the masses. Unlike my past approach, I’m not going to wear myself out trying to convince people that forced-air is terrible.