Not so sure how much of this is accurate, safe to say that Europe started to recognize these in the 1950s and not because of antiquated water systems and they certainly what not all "point of sevice heaters"
Also even in this article of the claim that tankless is more efficient is not 100% true. It's so close depending on application that even the US Dept of Energy is not claiming in all cases they are more efficient.
FYI I have nothing against them, heck my new home has one but I would be more than glad to have a tank again. It's kind of funny but here in the coastal Carolina's there is a HUGE more upscale community being built and using gas tank water heaters. It's almost a luxury item now, instead of a hot water tankless box bolted to the sides of the homes in so many new communities..
Let's look at the interesting history of this alternative method of keeping hot water flowing from the taps in a house.
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