Steam-heating history

DanHolohan

My buddy, Rick Taylor, sent me this history lesson. I had no idea.

Steamhead

Is the steam system in Radio City Music Hall still running?

DanHolohan

Yes, it's on ConEd steam.

EzzyT

Wow that's so fascinating.

Steamhead

Wonder if they'd do an All-Access Tour, to include the steam system?

DanHolohan

They do a tour of the theater, which is well worth the money. The stage does so many things and the Navy used it as a template for aircraft-carrier construction during WW II. In fact, there were soldiers stationed in the bowels of the theater during the war to protect against espionage.

As for the steam heat, when ConEd is involved, all you see is the line coming in from the steet, followed by a steam meter and two PRVs in series. I can show it to you at The General Society if you get to Manhattan. That building is worth the trip.

Pumpguy

Any pumping equipment? If yes, do you know any details?

DanHolohan

No pumps. ConEd steam in, and all the cooled condensate goes to the sewer. Some NYC water gets no respect.

jumper

I've seen numerous industrial facilities forgoing condensate recovery. And I've seen brave attempts to pump back the condensate. As an engineer I championed the latter. But now with hindsight I've changed my mind. Those boiler operators who dumped condensate were experienced.

Which brings me back to history of steam heating. Companies like DunhamBush have to sell stuff. But the best steam heating didn't use traps,vents,or pumps? Something like the ancient Moline design?

Pumpguy

DanHolohan said:

No pumps. ConEd steam in, and all the cooled condensate goes to the sewer. Some NYC water gets no respect.

Interesting there are no vacuum pumps. These can usually improve the efficiency and economy of "street steam" systems like these.

DanHolohan

Many ConEd-supplied steam systems have vacuum pumps. The Empire State Building is a good example. The vacuum pump allows the design engineer to downsize all the pipes, valves, and fittings because of the pressure-to-vacuum differential. The difference between ConEd steam and a boiler-provided steam is that ConEd doesn't want the customer to return the condensate. That would be very difficult since some of the customers would have to pump the condensate several miles under the NYC streets. There's no piping network for this and the transfer pumps would be enormous. I can't even imagine the size of the boiler-feed receiver ConEd would have to have to accommodate all that returned condensate.

I hope that makes sense.

jumper

Why do some NYC buildings use steam-to-steam generators instead of less expensive pressure reducing stations?

DanHolohan

Steam-to-steam generators?

jumper

DanHolohan said:

Steam-to-steam generators?

Yes. I've seen one in some NYC building. ConEd steam goes into a large tank & condensate drains out. Heating steam comes out from the tank & condensate from building heating system comes back to be reboiled by more ConEd steam. Controller for the ConEd steam looks similar to PRV. So that tank is a heat exchanger but I cannot see what the benefit is? Unless ConEd steam contains CO2 ? I doubt that.

In factories the advantage is that primary condensate is under higher pressure so easier to feed back into boiler. But when dumping steam????

DanHolohan

I'm not familiar with that application. Thanks for the heads-up.

Sailah

Was just doing some monitoring testing with ConEd in May. All their high pressure steam condensate gets dumped to the sewer on the distribution side too.

Can we do a trivia question because I was way off when I guessed?

How many steam traps does Con Edison have on their entire NYC distribution system? They are 90% 1" Thermodynamic & thermostatic traps BTW.

Winner gets something cool TBD

jumper

DanHolohan said:

I'm not familiar with that application. Thanks for the heads-up.

Don't like accusations without evidence. But is it possible some engineer specified steam-to-steam generator to increase project cost because his fee is percentage?

DanHolohan

Sure

Tom bates

They might have a need for clean steam, such as a hospital or maybe a brewery.

jumper

Tom bates said:

They might have a need for clean steam, such as a hospital or maybe a brewery.

Yes. But why is primary steam considered dirty? And it certainly is considered dangerous by health authorities.