German heating 100 years ago.

Published: May 1, 2014 - by Dan Holohan

Categories: History Lesson


I started going to the every-odd-year ISH show in Frankfurt, Germany in 1990 and haven’t missed one since. I feel quite comfortable in Frankfurt. So much so that there’s a barstool in Römer with my name on it.

One of the things I noticed right away about the Germans is that they are very precise in just about all that they do. I once asked a German engineer whether the term, “anal-retentive,” should  or sholdn’t have a hyphen. He didn't laugh.

In all the years that I've been visiting business city of Frankfurt, I've wondered whether the Germans have always taken their heating systems so seriously, or if this is something that came about after war, when the Allies afforded them the opportunity to rebuild just about everything.

I recently got my answer by way of a delightful article, written anonymously 100 years ago for one of the yellowed trade journals that sits in a pile in my office. This guy had a lot to say about the way heating in Germany was in 1913. I thought I’d interview him for you, and if you have any questions afterward, we’ll see if we can arrange a seance.

D.H.  So, my long dead friend, how do you find the hydronic business in Germany in this interesting year of 1913 when central heating is so new?

Anonymous In all the heating jobs I have examined at Berlin, and in many of the other cities of Germany, the fundamental principle of installation is identical with American practice. Almost all the jobs are water. There’s very little steam heating, excepting now and then in a big business block.

D.H. Cool! Are these all gravity hot-water jobs?

Anonymous The regular gravity steam or water job in Germany is the ordinary two-pipe work, with the same pitch as in America. The big hot-water heating installations frequently have a motor-driven, rotary pump in the return pipe for forced or positive circulation, enabling the use of smaller piping throughout and a disregard for the pitch of flow or return. This feature is also common practice in certain types of buildings in America.

D.H. Wow! And here I was thinking that the heating pump first showed up in 1928. I know that Louis Opländer, of Wilo fame, introduced the first one in Germany that year, and that Home Thrush, of Thrush Pumps, did the same in the U.S. Great minds tuned to the same channel, but those were centrifugal pumps and you’re talking rotary pumps for those earlier jobs. How about that! Hey, what about the average German contractor in 1913? What’s he like?

Anonymous He is an engineer, an expert having knowledge of the natural laws controlling gravity, combustion, evaporation, condensation, and friction. He is not an engineer perchance; he is an engineer perforce.

D.H. Okay, I’m going to give my 2013 American readers a moment to grab their dictionaries for that last bit from you, but while they’re doing that, tell me more about the contractors.

Anonymous Every single little hamlet, town or city, small or great, in the whole German Empire, abounds in Government buildings. All railroad stations, Post Office buildings, hospitals, schools, prisons, telegraph stations, War, Naval, Police, Governmental department buildings belong to the government and the government engineers embody in their heating specifications requirements that none but expert heating engineers can interpret. Further, this is the practice of German architects generally, who also in that through-going German fashion must, in their education, embody general engineering. So, to become a German heating contractor, necessitates knowledge of all the elements involved in the craft of heating and ventilating.

D.H. Architects who think like engineers. Imagine that! Oh, and by the way, does the term, “anal-retentive,” have a hyphen?

Anonymous (ignoring me) The German approaches each heating prospect with the deliberateness of an artist – subjecting each inside, outside, thin, thick, stone, brick wall, glass, sash, ceiling and floor to its known factor for heat loss, plus a known percentage for points of the compass for wind pressure, for double- or single windows. His answer is the exact size of each radiator, as well as the supply and return pipe necessary to take care of it exactly. This comprehensive procedure evolves a pipe layout of smaller diameters than obtainable on the average American job.

D. H. So in other words, the contractor who does his homework is going to come up with a job that uses less material that the contractor who wets his finger, holds it up to the four points of the compass for wind pressure, and then guesses.

Anonymous For certain.

 D.H.  You’ll be happy to know that 100 years from now, when you are residing in Stoney Lonesome, this will continue to be true.

Anonymous And the same shall apply to you, buster.

D. H. Tell me a bit about how they run their pipes. Many of the jobs I’ve seen in today’s Germany have the pipes inside the rooms. The thinking is that if the pipes are in the room there’s less of a chance of them freezing, and you can also spot any leaks before they can do lots of damage. These days in America, we’re ashamed of our pipes and like to hide them in the walls, where they both freeze and leak, thus creating high-paying insurance work for repair contractors. It’s all part of the American Stimulus Plan.

Anonymous The German contractor puts the pipes in the walls, but avoids all fittings. He dexterously and quickly, without flattening the pipes, bends them in every conceivable manner required. He has a small, portable forge with foot treadle for the blower as part of his tool kit. As many as six, long-turn bends, each in different directions, occur in one length of, say, three-quarter-inch pipe. All except the cellar piping is cemented into the brick or terracotta walls. The radiator connections protrude horizontally from the side wall, exactly in line with the radiator flow and return tappings. They never come up from the floor. The practice is to never have a pipe connection of any sort inside the walls.

D.H. That’s going to change. If fact, a lot’s going to change. You’ll see. Hang onto 1913 as long as you can.

Anonymous There is one other important feature about the German systems. In these custom-made, balanced, micro-metered, hot-water jobs, there is very little water, and it has got to move quickly to deliver its heat load to the radiation and get back to the boiler, as there is none in excess. This, and the balanced condensing surface, accounts for the prompt and sensitive regulation. These long-since-developed advantages of modulation and regulation are what have given warm-water heating its permanent popularity in all of Germany.

D. H.  A hundred years from now, they’re going to be using low-temperature water, produced by modulating-condensing boilers, moved by smart pumps, and controlled by something we’re going to call the Internet. The Germans will take all of this very seriously, as they did in your day, and I will go to visit them every odd year to see what’s new.

Anonymous You should check out this bar in Römer while you’re visiting. It’s been there for a long time.

D. H. Got it covered!