"Richard J Kinch" wrote in message
. ..
Phil Sherrod writes:

But before shutting it down, I decided to take some measurements and
calculate how much it costs to run an idle water heater.

Well done. I have performed similar experiments with similar results.
Idling losses are small. The tankless advocates are swindlers, but most
people don't have the critical faculties to understand the swindle.

Tankless take up far less space than a large cylinder, one its main
advantages. I have seen these used in commercial kitchen on faucets where
they are on for the best part of an hour. They can deliver 12 litres per
minute continuously and never run out. That is 720 litres per hour (190.2
US gallons per hour) running out of the tap. 190 gallons? that is quite a
size of storage cylinder you would need when a small white box on the wall
does it without taking up all that space.