The early days of district steam heating systems in NYC.

When I was a boy, we lived in Manhattan on East 79th Street, a half-block from the East River. My father worked at Glauber Inc., a plumbing-and-heating supply house that was directly across the street from our apartment building. I grew up playing on its loading dock.

During the winter, my father would take my big brother and I to Central Park, seven blocks over that way. We’d sleigh ride down Cedar Hill, which seemed huge then but really isn’t. The world went on forever in those days.

I thought about the long-gone boys on that hill on a hot day last July as I stood on the roof of a Fifth Avenue mansion just across the street from Cedar Hill. I was looking for evidence of a chimney that could have once served this incredible house but I couldn’t find one. And that made me wonder.

My father, my brother and I passed this house so many times on our way to Central Park. I never gave it a thought then. It was just another in a row of buildings that blended together like smoke from my father’s cigarettes. But on that day last July, I thought about the child who was father to the man, and I thought about the wonder of time and the generations of builders.

The general contractor asked me what I thought were the best heating options. The plumbing-and-heating contractor had invited me to join them that day and both had pretty much made up their minds (ductless mini-splits would win), but the GC wondered if it made sense to keep the steam system as well. Would it be a good backup for the new system?

The new owners should never be without heat - that went without saying - but a century of contractors had fiddled with that steam system and the GC wondered what it would take to get it running efficiently.

Oh, and I almost forgot to mention that Stanford White was the architect who designed this little palace.

I couldn’t resist.

So we’re up on the roof and looking for that chimney. Plenty of chimneys were there because this place was replete with fireplaces. But there wasn’t one where you would think one would belong had there once been a boiler in the basement. A couple of pressure-reducing valves were now down there. They came off of Consolidated Edison’s district-steam system. That’s how they were heating the place. The first PRV took the pressure from about 125 psig down to 50 psig, and the second took it down to the normal pressure of about 2 psig - standard stuff for district steam.

A room near the street once received the coal from the chute on Fifth Avenue and that’s what made me wonder whether there had once been a boiler, but the coal may have just been for cooking.

The Paul System

Then I wondered whether the house might have once had a steam engine. Some of the New York City mansions had these. The engine made electricity and they used the waste steam to heat the building. The radiators had me thinking this way for a while because each had an abandoned pipe that once took the air from the radiators.

The Dead Men called this a Paul System, after its inventor,Andrew Paul. He came up with what is essentially a tiny thermostatic steam trap that took the place of a radiator air vent. Each of these traps connected though a pipe to a manifold in the basement. The Dead Men created suction on the manifold and pulled the air from the radiators. When steam filled the radiator, the tiny trap closed and stopped the steam from entering the air line. In the mansions where they had steam engines, the Dead Men usually used a steam-powered ejector to produce the vacuum.

I once stood in the footprint of one of these engines at the Dakota Apartment, which squats directly across Central Park from this building. The Dakota is famous for being the place where John Lennon lived and died.

But a steam engine also would have needed a chimney and we couldn’t find that chimney, so I kept wondering and poking around. I love poking around.

In the basement, there was a room that used to be the laundry and they had these 7-ft.-tall racks that pulled out on rollers from a chamber that was walled with big steam pipes. How’s that for a clothes dryer? The mansion is seven stories tall and the top two floors were for the servants. A root cellar and a wine room were located in the deepest basement, as well as a prep kitchen. There was an elevator for those who didn’t want to climb the grand staircase, and dumbwaiters for the food, the firewood and the coal.

The radiators in the servants’ quarters were free-standing and cast-iron with a hand valve on each side and that now-abandoned air line from the days of the Paul System. The radiators serving the lower five floors were hidden. The Dead Men called these “indirect” radiators. They hulk inside wide ductwork and warm the air that comes in from the outside through a sidewalk grate that connects to a large plenum.

The house also could recirculate air from upstairs. It works like this: At the bottom of the grand staircase, which rises seven stories, there’s a door that has very fancy metal latticework. Open that door and you’ll find the gaping maw of the return-air duct. So the indirect radiators heat the outside air, which rises by gravity through the ductwork and enters the rooms on the lower five floors of the mansion. The cooler air tumbles down the hollow center of the grand staircase and though the latticework of that fancy door.

From there, it makes its way back to the basement through return ductwork. It mixes with fresh air from the outside and rises again. There’s also an old humidification system connected to all of this. I was smiling like a kid with a Flexible Flyer.

Later that day, when I was back in my office, I looked though a book in my library titled, “Fifty Years of New York Steam Service,” which Consolidated Edison had published in 1932. I came across a section that explained how, in 1886, after laying five miles of pipe in lower Manhattan and having secured 350 commercial customers, the New York Steam Co. decided to expand its service uptown. It built a boiler plant on Madison Avenue and ran pipe up and down that famous avenue and also over to Fifth Avenue, where they might serve the mansions that America’s millionaires were then building.

The book lists the first customers to sign up and it reads like a social registry for the time. John D. Rockefeller wrote, “I have had my house heated for several years by steam supplied by your company and am satisfied with the services given.” A blizzard shut down New York in 1888, making it nearly impossible to move anything though the streets for weeks, including coal. The steam company’s customers stayed warm throughout the blizzard and district heating became even more popular in the years that followed, during which Stanford White designed the house by Cedar Hill.

I had my answer about that missing chimney. There had never been one.

After I had my fill of poking around, which took most of the day (you would have done the same), I explained how some steam traps work and some new air vents would put the steam system back into good working order, which would give the homeowners a wonderful backup for the new mini-splits. The family of three who had just purchased the mansion for $44 million, and who would now pay millions more to get it into shape, would be cool in the summer and warm in the winter and I would have a fine story to tell you here.

Before heading back to Penn Station to catch the train home, I crossed the street and climbed Cedar Hill. I looked back at the big house and I thought about my long-gone father and all that he had taught me. I thought about how a boy with a sleigh can pass such a mansion so many times and not ever notice it. And I thought about the wonder of time and the generations of builders, and how much I still want to see and consider and learn.