A few years ago, an engineer who works with older New York City buildings started to email me with good questions, mostly about steam heating. I’ve enjoyed hearing from him because he’s not afraid to ask questions, and he’s also not afraid to admit he doesn’t know everything. I like that because I don’t know everything either.
When we first began exchanging emails, he was convinced that big buildings didn’t need much steam pressure. He had come to a seminar I had done in New York City, where I had mentioned that the Empire State Building gets by with about 1 1/2-psi steam pressure on most days. That didn’t seem possible to him at first. It didn’t seem possible to me either when I first heard it. But then, I learned that it’s not the pressure of the steam, but its latent heat that gets the job done. And there’s plenty of latent heat in steam, even at just a few ounces of pressure.