Hydronics, Italian Style
If you ask seasoned heating pros about the largest trade show for hydronic heating in the world, most will tell you about the ISH show held in Frankfurt, Germany, every other year. ISH Frankfurt is the largest show of its kind in the world and is a great venue to view the latest in worldwide hydronics technology.
A lesser-known but still very impressive trade show dealing with HVAC and plumbing takes place in the years between the ISH Frankfurt shows. It’s called Mostra Convego Expocomfort (MCE) and its home is the massive Fiera Milano grounds in Milan, Italy.
This past March, I had the opportunity to spend four days at the event, which occupies about 1.7 million square feet of exhibition space. Here’s a summary of some of the unique aspects and offerings at the show.
European HospitalityIf you like fine foods, there’s no better place than Italy to indulge yourself. Risotto, carpaccio and prosciutto are among my favorites. The way Italians prepare goose, rabbit and even donkey meat makes you savor every bite. Combine this with any of their wines and a three- to four-hour relaxed dinner experience beginning around 8:30 p.m., and it’s obvious they know how to leave work behind at the end of the day.
This penchant for food shows up at the trade show as well. Walk by most booths in the morning and you’ll find cappucino freely available. At lunch there are plates of sandwiches, and by later afternoon some of the booths offer complementary beer, wine and juices. The bigger booths even include lounge areas with waiters. It’s a delightful contrast to standing in lines to purchase $6 lukewarm hot dogs and $3 sodas at some North American trade shows.
Solar EverywhereThe use of solar thermal energy is increasingly popular in Europe and this was certainly reflected in the products seen at the show. Almost every company selling some type of hydronic heat source, such as a boiler or heat pump, also offers solar thermal collectors and related hardware to tie those collectors into a system along with other heat sources, as seen in the schematic of Figure 1. The vast majority of the solar thermal systems that were on display at the show use a closed-loop piping circuit filled with antifreeze between the collector array and storage heat exchanger. Both flat-plate and evacuated-tube collectors were in abundance.
'Sputnik'That’s the description uttered by one American to describe some of the multipurpose tanks on display. The naming was no doubt inspired by 20 or more piping connections coming from the side of the tank in all directions (see Figure 2).
In some cases these connections go to heat exchanger coils for domestic water, some for space heating and some for heat input from solar collectors, heat pumps or solid-fuel burners. The tank itself serves as a central buffering mass for the system. Such tanks are typically shipped and installed without insulation. The latter is added as a flexible wrapper with foam insulation 3- to 4-inches thick and a heavy-duty zipper. This allows larger-volume tanks to pass through narrower doors and then be well-insulated on the jobsite.
It’s simple and appropriate, and something we should do in North America, especially with the need for larger tanks in solar thermal combisystems.
Rack 'Em UpAnother repeated theme was multiple modulating/condensing burners mounted to a common frame, as seen in Figure 3.
Half the boilers face in one direction and the rest in the opposite direction. Each cabinet supported by the frame contains one or two independent burner assemblies. The number of circulators under the cabinets tells the story since each burner assembly has its own circulator.
The setup shown in Figure 3 is typical. It includes four cabinets, each with two burner assemblies. All boilers connect to flange-connected headers at the bottom. The headers connect to a hydraulic separator, which allows the boiler system to interface to the distribution system without creating interference between the boiler circulators and the system circulator(s).
The boilers all connect to a polypropylene “common vent” at the top. Each vent connection includes a special check valve to prevent flue gases from migrating into unfired boilers. Look for this type of venting to begin appearing in North America.
Such multiple-boiler configurations offer a relatively small footprint, high turndown ratio, high seasonal efficiency and easy serviceability. The benefits ensure that such a paradigm will continue to capture market share in Europe and North America.
High-Efficiency CirculatorsThe Europeans rate the energy consumption of circulators based on a standardized test protocol. The scale works just like report-card grades in school (i.e., an “A” is better than a “B,” etc.).
The current state-of-the-art is an “A” rating. Only circulators using permanent magnet, electronically commuted motors are capable of achieving this rating. The more common wet-rotor circulators with permanent split-capacitor motors now used in Europe and North America fall at a “C” or “D” on this rating scale.
An example of a small high-efficiency circulator having multiple operating modes is shown in Figure 4. Some European models of such circulators have peak power consumptions under 25 watts.
Interestingly, two even higher efficiency ratings, “A+” and “A++,” are scheduled to come into effect during 2013 and 2015, respectively. Manufacturers are already preparing products to meet these efficiency targets.
Designer RadiatorsIn Europe, and especially Italy, radiator design has become a form of contemporary art. The ability to combine metal with cast polymers has allowed for even wider forms of expression, as seen in Figures 5 and 6.
Figure 7 shows a radiator constructed entirely of polypropylene tubing and headers with brass inserts for threaded piping connections. A wide range of sizes and colors are possible.
Box ItEuropean hydronics manufacturers like to combine hardware into modules. It’s evident with boiler systems (such as shown in Figure 3). It’s also seen in other products such as the combination of a boiler assembly, storage tank, heat exchangers, mixing devices and controls seen in Figure 8. Even if you don’t read Italian, the display is mostly self-explanatory: An array of solar collectors supplies heat to a storage tank in the vertical cabinet. This cabinet also contains the boiler assembly and heat exchangers for domestic hot water. Heat is then sent to a metering station (seen recessed into the wall). From here heat is sent to both radiant panels and panel radiators at two different temperatures.
Familiar NamesAmericans roaming the MCE event will typically find booths for companies well-established in the United States. Examples include Riello, Oventrop, Caleffi, Viessmann, ITT, Grundfos, Wilo, Uponor and Viega. In most cases, these booths are significantly larger than would be found at U.S. trade shows.
Boiler With A BrainFinally, Figure 10 is an artistic interpretation of a “smart boiler.” How would you like to walk into a dark basement and shine your flashlight up at this for the first time? I’m sure it was created to draw attention at the booth. It certainly drew mine.
After viewing all this hardware, one might conclude the European approach is far superior to methods used in North America. I don’t feel this is necessarily the case.
Fundamentally, both markets are trying to accomplish the same thing - space heating and domestic hot water using the least fuel possible. The Europeans pay a premium for their fuel (regular gasoline currently sells for about $6/gallon), and this definitely drives the market for widespread inclusion of renewable energy.
If you’ve never been to a European heating trade show - either ISH or MCE - I urge you to consider the trek. Several manufacturers doing business in both Europe and the United States regularly invite customers to such events. It’s an eye-opening experience and, oh, did I mention that the Italians really know how to eat?