Oi vei, the rebbe is silent and the talmidim bicker. ROB, laws of physics are not to be denied, but they work best when you don’t confuse them.
In a typical tank water heater or in boiler coil, if the inlet is shut, there can be no outfow without drawing a vaccum.
Water finding its level is a concept in an open system, not in a pressurized, closed system.
Fixed volume rigid system in which water is heated must have expansion capacity. Hot water heating boilers typically have an expansion tank. A take can only expel what it took in, and these generally have nothing to do with the domestic hot water.
In a heated tank, the hottest water will accumulate at the top. If the burner or element is off, and cold water enters at the bottom, and stays there until a thermal drift cycle mixes it in to the hot. This can’t be seen and not well predicted and thus not relevant.
The ONLY WAY to use hot water from a basement tank is to
A)have the tank below yad soledes and use in a normal manner with the heating element or burner OFF. A limited supply of lukewarm water.
B) To attach an alternate pressure source, that wont be mevushal, such as air pressure vessel, or air compressor loaded, but shut off. The air entering the tank will drive the hot water out, instead of the cold water (with cold vavle off)
C) to have a gravity flow system, with the tank above the point of use (Kithcen) and a vaccum relief to let air into the tank as the hot water exits. This does not work too well if the hot outlet of the tank is at the top, as in an American type water heater. IOW, this need to be purpose-built by someone who knows what he/she is doing.
ROB, are you referring to some European setup?
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