Some findings from ISH 2011


Copyright 2011, J. Siegenthaler, all rights reserved
Visit John's website at www.hydronicpros.com

This past March, I was fortunate enough to spend four days in halls 6 through 11 of the International Sanitation and Heating Expo, known to most as simply ISH. This event returns to fairgrounds in Frankfurt Germany every two years. Most hydronic professionals consider ISH as this planet?s preeminent event for viewing the latest in heating and plumbing technology. This show drew over 200,000 attendees, making itover three times larger than the AHR show held each year by ASHRAE. I can vouch forthe fact that this show covers lots of real estate. I walked countless miles over the course of those four days, and my focus was only on the heating and cooling aspects ofthis show. There were also hundreds of booths in other halls dealing with the plumbing products that I had no time to visit.

Common Theme:

The European heating market continues to be driven by pervasive commitments to lowenergy use, reduced emissions, and environmental stewardship. This theme was evident at nearly every booth. Here?s a summary of a few key findings that echo that theme:

Caleffi was show casing their new products for solid fuel boilers. One of these products provides flow between the boiler and a storage tank, while at the same time preventingsustained flue gas condensation within the boiler. The latter is done using an integral thermostatic mixing system. These units also allow passive circulation of hot water fromthe boiler to the storage tank during a power outage. Functional, compact, and elegantly made - I like all three.

Figure 1

Caleffi?s new circulation module for solid fuel boilers


Combi-systems Everywhere:

Besides their usual offering of wall-hung condensing boilers, the major heat sourceproviders (Viessmann, Buderus, Vaillant) were all showing well thought outcombinations of heat pumps with other heat source as pellet-fired boilers, solar thermal subsystems, and even micro combined heat and power units (MCHP).

The Europeans have a flare for elegant industrial design. It?s common to see devices such as boilers or heat pumps housed in cabinets that give little clue to their internalworkings. Figure 2 is a good example - It?s a water-to-water heat pump with an internal buffer tank manufactured by Vaillant.

Figure 2

A residential water-to-water heat pump from Vaillant Most of these combi-systems featured a storage tank, known in Europe as a “thermal accumulator.” The high thermal mass of this tank serves as a moderator between the intermittent heat input from solar collectors, solid fuel boilers, or off-peak electricity, anda highly zoned distribution system.

Figure 3 shows a setup by the Schuco. The device on the right is the outdoor unit of an air-to-water heat pump. It was piped to the central control module seen in the lower middle of the photo. This module connects to the wall hung boiler and a generously sized thermal accumulator tank seen at the far left. The central unit manages heat input from either the heat pump or boiler, heat exchange with the buffer tank, and zonecontrol. The fit and finish of these products is remarkable. It?s easy to visualize them neatly integrated into the laundry area of a European flat.

Figure 3

Air-to-water heat pump / wall hung boiler / thermal storage combi-system by Schuco

The capacity of residential heat pumps in Europe is relatively low. Thermal outputs of 6to 9 KW (e.g. about 20,000 to 30,000 Btu/hr) are typical, and appropriate for smaller living units (flats, condos, or small energy conserving houses).

Wilo was showing its Stratos PICO circulators (figure 4). This is their current flagshiphigh efficiency circulator for single and dual family housing in Europe for the next fewyears. The smaller PICO model tops out at 20 watts power draw at full speed, and canoperate as low as 3 watts electrical input at minimum speed. To put this in perspective,the full speed power requirement of this circulator is less than 10 percent of the power drawn by circulators that simply push water through the heat exchangers of some North American mod/con boilers.

Figure 4

Wilo Stratos PICO circulator

This product will meet a very stringent European circulator efficiency standard set to go into effect in two stages ( Jan 1, 2013, and August 1, 2015). After the 2013 date, it willbe illegal to sell standard PSC-based wet rotor pumps in Europe. It appears that what we know as the standard wet rotor circulator with permanent split capacitor motor, is soon to disappear from new European installations. I asked about this circulator comingto North America. While I didn?t get a no, the answer suggested it?s not likely anytime soon.

Wilo was also showing it “Geniax” decentralized pumping system. The concept is simple: Use a separate variable speed micro-circulator to control flow through each heat emitter based on room comfort settings. From what I could gather this is still in very limited distribution outside of German. A complete 10 circulator system with controls was estimated at $5000 Euros (pretty expensive).

Figure 5 shows two of the micro-circulators mounted on the upper manifold. The two corresponding devices on the lower manifold are check valve. The white vertical column to the left of the manifolds is a very small hydraulic separator that keeps thesmall differential pressure created by the micro-circulators separated from any other pressure differentials induced at other locations within the system. Don?t expect to see this product in North America anytime soon.

Figure 5

Two-zone Wilo Geniax micro-circulator system with very small hydraulic separator column at left. Black devices on lower manifold are check valves.

Lowara (a division of ITT) was also showing it new “Auto” and “Vario” circulators, whichwill be available in the US later this year through Bell & Gossett. The “Auto” circulator operates in proportional differential pressure mode. The “Vario” circulator has a dial for setting its speed over a wide range. Both of these circulator use high efficiency ECM motors controlled by microprocessors. Such circulators could be likened to computers.With a change in firmware, they can take on “multiple personalities.” This allows the potential for them to work in a wide variety of specialized applications such as drainback



You would expect the largest plumbing and heating show on earth to have a fair amount of tubing on display, and ISH 2011 was not disappointing in this regard. It?s very evident that copper tubing - what many in North America consider to be the staple of hydronic tubing - is now any but the staple in European hydronics. Although there was somecopper tubing on display, polymer tubing options such as PEX, PEX-AL-PEX, PP-R,and others now seem to dominate the market, especially in smaller systems. Uponor was showing large diameter composite PEX-AL-PE (nominal 4” size) as seen in figure6a. This tubing is jointed using crimp-type fittings. See figure 6b.

Figure 6a

Large diameter PEX-AL-PE composite tubing from Uponor Figure 6b

Stainless steel press fittings used to join large diameter PEX-AL-PE composite tubingfrom Uponor

One of my more interesting finds was the German company Multitubo Systems. They were introducing a heat fusible PE-RT (polyethylene, raised temperature) compositetube and fitting system. The composite (PERT-AL-PERT) piping is rated for 10 bars (147 psi) pressure, and 95 ºC (203 ºF) temperature. PE-RT is not a crosslinked polymer. Unlike PEX, it can be remelted and reshaped. This allows the tubing andfittings to be joined by socket fusion (see figure 7). The inside of the fitting and outer surface of the tube are heated using a simple electrically-powered tool, pulled apart,and immediately pressed straight together for a permanent bond. I was able to try this myself, and can vouch that it?s pretty easy. I see this offering as a simple and low costway to permanently bond together pieces of tubing for longer circuits without reliance onmechanical couplings. Word is that it?s likely to find its way to North America soon.

Socket fusion of PE-RT composite tubing and fittings being shown by Multitubo Systems


Well Grounded:

Several manufacturers were showing geothermal manifolds (Figure 8), and manifold“pits” (figure 9). Geothermal manifolds are made of engineered polymers that easily handle the pressure and temperature requirements of earth loop circuits. Their diameters are configured for significantly higher flow rates compared to manifolds for radiant panel heating systems.

Manifold pits are water-tight enclosures, typically made of polyethylene, designed to be buried with their access cover flush with finish grade. They have several stubs of HDPEtubing welded through their sidewalls. Installers simply heat fuse HDPE earth loop circuits to these stub outs. Internally, they contain a large diameter manifold withindividual flow setting and isolation valves for each circuit. The access cover is fully gasketed to make the unit water tight.

Example of a manifold for earth loop circuits

Figure 9

An earth loop manifold pit shown by the German company Frank GmbH


I could have taken hundreds of photos of the designer radiators shown at ISH, and stillnot cover them all. While there were certainly new artistic impressions, (see figure 10), I didn?t see anything radically new with perhaps one exception: Kermi showed a dual water plate radiator in which all flow passes through the front panel first, and thenthrough the rear panel. This panel offers about the same heat output as other dualwater plate radiators, but reduces heat loss to the exterior wall due to lower rear surface temperatures.

Figure 10

One of hundreds of designer towel warmers shown at ISH


Good looks & High Performance:

The top floor of hall 9 at ISH is reserved for showing solid fuel heat sources. You?ll find hundreds of products ranging from wood-fired cookstoves, to high-technology wood-gasification units. Many of these units are operating! They?re connected to overhead venting systems to carry flue gases out of the building. Most of those designed for hydronic systems are piped to large banks of radiators that just dissipate the heat being produced. Needless to say this is the “hottest” floor of the trade show.

The device shown in figure 11 caught my eye. It?s a wood-gasification boiler withaesthetic details that make it worthy of sitting in your living room. You can just pull up achair and watch the gasification process convert firewood to heat at efficiencies of 90+ percent through the clear ceramic glazing in the lower chamber.

Figure 11:

An “Appearance grade” wood gasification boiler by Wallnorfer

You Gotta Go - at least Once:

What I?ve shown you is but a glimpse of what?s on display at ISH. If you?re into hydronics or plumbing, and have never been to an ISH show, I highly recommend youmake the trek. The next one will be in March 2013. If you have attended this show, you can surely relate to some of the novel hardware shown above.


I?ve had opportunity to visit several ISH shows, as well as other European heating andplumbing trade shows over the last few years. While always interesting, I have to admitthat there is still plenty of “carry over” concepts and products from one event to the next(as there is with any trade show).

Ultimately, I?ve concluded that these events show different products aimed at markets very different from those in North America. All the technology on display could beproduced and sold in North America, if and when energy prices (think $9 per gallon for unleaded gas), and cultural mind-sets (think environmentalism as a quasi religion) occurover here. We?re not there yet, nor am I suggesting we should be.

Still, some of what you will see at ISH will inevitably work its way into future NorthAmerican product offerings. The ultimate goal remains the same: Deliver unsurpassedcomfort using the least resources possible.


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