This article was originally published in the November/December 1995 issue of Home Energy Magazine. Some formatting inconsistencies may be evident in older archive content.



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Home Energy Magazine Online November/December 1995


Oh, How I Wish
You Could Have Seen ISH!

by Dan Holohan

I traveled to the ISH (International Sanitation and Heating) fair in Frankfurt, Germany, last March with a few friends who, like me, had been there several times before, and a few others who were making their first trip to this Oz of plumbing and heating.

There was no way I could have prepared the newcomers for the experience.

How big is it? one friend asked.

Don't worry about it. Just bring good shoes, I told him.

No seriously, how big? he persisted.

Did you go to the ASHRAE show in Chicago? I asked. He nodded. ISH is about five times bigger than ASHRAE, I told him. There are 2,013 exhibitors this year, and 230,000 visitors from five continents will walk through the ten buildings that house the show in the five days it's open.

Good shoes, eh?

Real good shoes.

Culture Shock

If you've ever pulled into a gas station in Europe, you know these folks are serious about energy conservation. And since the late 1980s, they've become equally consumed with the environment. This is easy to understand considering what they found when the Iron Curtain tumbled. Much of Eastern Europe, they quickly learned, was an environmental wasteland. It would be like the people of Ohio waking up one morning to find that Pennsylvania no longer had any trees. It would make you want to do something, wouldn't it?

Today in Europe, they do something. For instance, if you lived in Germany right now, you could expect a visit from the Chimney Sweep every six months. The Chimney Sweep is a government employee who arrives unannounced at your house and does a combustion efficiency test on your boiler. You have to let him in; you have no choice. If your boiler passes the test, the Sweep gives you an official sticker that allows you to use your boiler for six months.

What if your boiler doesn't pass the test? I asked upon learning about these curious inspections from a German citizen.

You have two weeks to have the boiler fixed, she answered.

And if you don't comply? I wondered.

They come back and take your boiler away.


With a truck, they come, she said, emphatically nodding her head. How's that for a government program with teeth?

Two years ago when I made my pilgrimage to ISH, I heard rumors of a new type of boiler that would operate at low temperature while emitting 0% nitrogen oxides (NOx). This mythical boiler was still in the idea stage at the time. It seemed nearly impossible. This year at ISH, I saw that boiler in full operation right on the show floor. Sure, it's still about three years away from the European consumer, but there it was, and boy, did it gather a crowd! A computer read out the emissions from this natural gas, catalytic-combustion boiler, and sure enough, the NOx reading held steady on 0%.

A Wonderland for Wetheads

One of my favorite things about ISH is that they fire many boilers on the floor. They also put tiny TV cameras in the combustion chamber so you can watch the flame. Then they show you what's happening on big display boards plugged into computers. It's like EPCOT for Wetheads. If you're into hydronic heating, there's no better place to be than ISH.

And everyone's a Wethead in Europe. Boilers heat literally 100% of their buildings. By contrast, boilers heat only about 6% of North American buildings. It's because of this huge market share that European boiler manufacturers can afford the research and development necessary to give the world this incredible technology.

Here you'll find not only the new catalytic-combustion boilers, but also a world of condensing boilers of both the gas- and oil-fired variety, as well as blue-flame, low-NOx-producing oil burners, which one manufacturer admitted was like owning a Ferrari when it comes to maintenance. Many boilers hang on the wall and take no more space than a medicine cabinet.

Because of their sensitivity to environmental issues, European manufacturers have developed filters to neutralize the liquids that drip from condensing boilers. One company dripped the fluid through a filter and into a tank containing tropical fish. The fish seemed completely unaffected. Another manufacturer showed a plastic flue pipe system for condensing boilers. I asked where the plastic came from and was told they bought it from U.S. recycling plants. It seems they're using our old soda bottles.

European boilers are also physically beautiful. They're packaged to look like appliances, and I wouldn't mind having any of them in my living room, let alone my basement. Several manufacturers go to the trouble of airbrushing wonderful designs on their boilers. And this wasn't just for the show; these were production items.

But before you run out to buy any of this beauty or technology, you should be aware that few European manufacturers bother with the U.S. market. Our choices are limited because our market is so small. And besides, who but the most environmentally conscious people would pay the price for a catalytic-combustion, low-NOx boiler while living in a land where in many places the government says it's perfectly fine to burn old tires in your fireplace?

Plenty of Water

You won't find any U.S.-style direct-fired, high-volume water heaters at ISH. Europeans opt for either indirect heaters, which sit next to or under the boiler, or wall-hung, low-volume instantaneous heaters. Many North Americans have become familiar with indirect water heaters during the past five years or so. More manufacturers are offering their versions of these indirect-fired storage tanks. Packaged-boiler manufacturers are now also offering indirect heaters.

A boiler treats an indirect water heater as just another heating zone. The indirect heater, which is basically a very well-insulated storage tank, has an internal coil through which boiler water flows. It might also be a tank within a tank, with the boiler water flowing around the outside of the inner tank (which contains the domestic hot water). It has an aquastat that senses the domestic hot water temperature and, through a relay, starts and stops the burner and the circulator. You wind up with all the hot water you need, and the boiler suffers less of a standby loss.

The main difference between the European and North American versions is the look (theirs are prettier), the insulation (theirs is thicker), and the materials of construction (more of a choice in Europe, including all-copper).

But not every European home uses an indirect water heater. You'll also find small, point-of-use heaters under many European sinks, as well as wall-hung, direct-vent instantaneous water heaters. This is a technology that has been available to the North American market for some years but hasn't caught on for reasons I'll never understand. I think wall-hung heaters have great merit. This is a product that people concerned with energy conservation should explore more fully.

The wall-hung heaters available today can easily and instantly fill even a hot tub with a never-ending supply of hot water. They've more than proven themselves under the most challenging conditions. At the 1994 Woodstock festival, for instance, the promoters used 20 of these heaters to provide 5,000 showers a day for the festival's employees (this at the insistence of the town of Saugerties). They never ran out of mud at Woodstock, but they never ran out of hot water, either.

The one drawback to most of the gas instantaneous water heaters currently available is that the pilot light wastes an amount of energy equivalent to the standby losses from a storage water heater. If they would just eliminate the pilot, instantaneous water heaters could save a lot of energy.

As for saving water, Europeans are famous for their low-flow presentation platter toilets. I've seen plenty of these and have to draw the line in my own mind right there. There's a question of quality of life that I have to consider at my age, and these things just don't inspire me.

Several companies displayed a system that collected rainwater in a huge, buried plastic tank, and this was interesting. Once collected, the rainwater became available for the home's toilets and clothes washer. It is a sensible way to save water without offending the senses.

Indoor Air Quality

As to their homes, Europeans keep things buttoned up tightly. Everywhere you look there are new windows. Even the oldest buildings have modern, high-efficiency windows.

Why so many new windows? I asked.

The government subsidized them for years, like your solar program, I was told. They also did the same for boilers when we were trying to get rid of the old ones.

In Europe, there's been an emphasis on air-to-air heat exchangers in recent years. In fact, this was a hot topic when I visited in 1991 and again in 1993. I learned then that most of this technology was coming to them from the United States. They are years ahead of us in hydronics, but the reverse is true when it comes to HVAC. One of my traveling companions, a second-generation HVAC contractor from New York, was not impressed by anything they showed him on the air side of things. They're at least 25 years behind at this point, he told me.

I did see one thing that struck me as a blast from the past, however. Nearly all Europeans use flat panel radiation. These radiators work with a low flow of turbulent water and a relatively low temperature (167deg.F, maximum, by law). They run their pipes outside the wall (usually masonry or concrete) and no one seems to mind. One radiator in particular caught my eye because it was on a hinged fitting that allowed it to tip away from the wall. Behind the radiator, and inside a metal box, was a screened opening that led to the outside.

What's this? I asked.

This is a new way of warming the air as it enters the home, a salesperson told me. It's simple! The air comes in here from the outside through this screened box. Then it touches the hot surface of the radiator and rises into the room. He smiled. A good idea, no? It's brand new!

I thought immediately of my old heating books from the turn of the century where, illustrated with pen-and-ink charm, I can find this very same principle. Back then, they called it indirect heating. Its purpose was to protect the occupants of the home from the evils of poor air quality.

Pumps, Pipes, and Radiators

There's a standard way of installing hydronic heating in Europe. Building codes and laws regulate much of this. You start with a boiler. The boiler has a small computer that tells it what to do on any given day. The computer senses outdoor and indoor temperature and resets the water temperature to match the heat input to the building's heat loss from moment to moment. The newer boilers are connected to the factory through a cellular communications network.

All circulators run continuously. Most radiators have thermostatic radiator valves, making each radiator its own zone. There is always a differential-pressure bypass valve in the boiler room to give the continuously flowing water a place to go should all the radiator valves close at the same time.

The piping is either steel or plastic. They bend elbows and weld tees rather than using threaded or soldered fittings. Pipes run from the boiler to the manifolds, which are located in key areas throughout the home. The radiators pipe off these manifolds.

About 25% of the homes have radiant floor heating. Cross-linked polyethylene (PEX) is the standard pipe nowadays and it has become a commodity. The emphasis now is on the means of connection from the plastic pipe to the manifold's metal fittings. I saw many new and interesting ways to do this at ISH. I expect to see these same methods showing up here in the United States before long. It's good stuff.

The most startling items at the show are the radiators. At ISH, radiation approaches an art form, and this year they pushed things further than ever. The colors, shapes, and styles are creative and wonderfully playful. With each visit, I see more of these beautiful panel radiators, but there's more than good looks going on here. Since they work on low temperature, panel radiators also save energy. They are pricey, however, so look for them to show up in high-end homes first when and if they finally arrive in the United States in force.

Lessons Learned

I always return from ISH with a certain sense of sadness, knowing that most of what I saw will never reach the North American consumer. In this country, we seem to be satisfied with products that are good enough for the market, and I have to admit, I can fully understand this. Take boilers, for instance. In the United States, we produce boilers that burn fuel at relatively high efficiency with relatively low emissions. They seem to be good enough. Although U.S.-made condensing boilers do have a small share of the market, most consumers probably won't pay two or three times the price for a few more efficiency points or zero emissions, unless our government forces them to.

I asked the group of contractor friends who had accompanied me to ISH how much higher the price of a boiler could be, considering the North American consumer and the available European technology. They agreed that 20% was a reasonable figure. They could sell the higher technology, but not if the price was more than 20% higher than the American offering.

As to panel radiation and floor heating, this group was very enthusiastic. My friends thought these items were very salable. But here again, I knew that most of what I admired would never come our way. Our market is simply too small to generate interest.

Dan Holohan is a writer and speaker based in Bethpage, New York, and author of The Lost Art of Steam Heating.


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