Is there a way to refill an evacuated water supply reservoir from an elevated water supply tank, without using any valves, but only the power of gravity?
I already know that a siphon is needed to start the flow from the elevated supply tank, but I do not know how to push the air out of the lower reservoir, send water into it, and then retain the water without admitting air through the water fill tube or air communication tubes.
Also, where would be a place to look for possible solutions to these questions? I have researched the technology of intermittent dosing siphons for sewer flush systems from the 1880's before electricity was widespread, and I know that air communication tubes can be extremely complex and dynamic in operation, but there is apparently no formal way to describe it.