Originally Posted by
Gunnar Alquist
There is a retirement community nearby that used water cooled (!) air conditioners. These date from the 1960s and, to the best of my knowledge, have all been replaced by now. No, not evaporative/swamp coolers. These were air conditioners that used a controlled stream of water flow to cool the condenser coils. As you can imagine, they used a lot of water. A solenoid valve would allow a steady stream of water as long as the condenser was running. The condensers were fairly small and generally installed in the garage attic.
If what you are describing is what is common in condos in South Florida (sounds like it is), then the terminology would be "package units" instead of "a/c condensers".
It is common to use water-to-air heat pumps with chiller systems for a/c, and boilers come on to make them into heat pumps.
They are package units with connection to chiller risers, there is a compressor in them, they are installed in most high rises instead of split system a/c condensers / air handlers.
I am envisioning that Aaron found a straight up "condenser unit" designed for outdoor use in that attic.