I've figured most of it out, but I don't know what to call it, or where to
study up on it in order to restore/augment it.
4x10 water panels on the roof.
huge tank / box in the cellar
in line pumps delivering water to the panels, with relief valves (I believe
this is called a drainback system?)
pipes running to the wood stove
pipes running to the spa
pipes running to the hot water heater
water fed in through a line from the house main
Digital controller with sensors located at all of the above.
best I can figure from watching it run (when it ran) is this
Thermal production is sensed at stove or panels - system circulates, heating
up the tank (is there a coil in there?)
Thermal requests are honored by incoming water passed through (the coil) on
its way to the water heater.
The spa water passes through there when ever it is running.
All of it seems to have fabulous potential, but I don't know what to call
Some good links or book suggestions appreciated.