Ray's Hot Water Mystery

Oct 26, 2019

RAY: A few weeks ago, my wife and I had occasion to visit New York City and stay at one of the finer hotels—you know, one that actually had beds and sheets.

I'm sure all of you have noticed this: If you go into the bathroom in your hotel room and turn on the hot water, you get it very nearly instantaneously. So, I'm convinced that the water heater has got to be under the sink, which is called a "point of use" hot water heater. I immediately drop to my knees, and I'm on my back looking up under the sink and I see nothing.

So, I decided to investigate. I walk up and down the corridor, figuring somewhere there's got to be a "Mechanicals" room where the water heater is, and it's obviously going to be right near my room. All night long I'm tossing and turning. I can't figure this out.

At 2:00 in the morning, I jump out of bed and run to the room next door. I know this is the utility room. It's not a real hotel room, it's a phony room. I pound on the door, expecting no one will answer. A guy opens the door in his underwear: "Whaddaya want?" So, I know that's not the answer.

The next morning, I ask one of the chambermaids, "Where is the water heater on this floor?" She says, "There's no water heater on this floor." I ask the concierge, "Is there a water heater above us or below us?" He says, "No, monsieur. All ze water heaters are in ze basement."

So the question is, if the water heaters are in the basement, and I'm on the 11th floor, how can I have hot water instantaneously?



RAY: The water heater is in the basement. All of the hot water faucets are connected to the same pipe that goes to the first floor, second floor, third, so they're in series.

Let's say there were let's say 12 floors in the hotel, and I left the hot water faucet dripping in the bathroom of the 12th floor, then the pipe would constantly be full of hot water because it's supplying that 12th floor bathroom.

If the water ran down the drain at least it would do so and supply hot water to everyone else. But in fact they're more clever than that. And they don't have the water dripping and going down the drain. They have tapped into that pipe right at the very top. With a little pump they take that water that would ordinarily go down the drain and they pump it back to the hot water heater, so the water is constantly circulating and never more than a couple of feet away, no matter what floor you're on.

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