Looks like the water heater at my sister’s house had a type of circulation system. After I tested for leaks all was fine. At least that is what it seamed! When the cold water.was turned on water came out the hot water supply line. The cold water inlet was capped,b the hit water out line is some how connected to the cold. Nevertheless, although I brought the shop vac back over it was not needed. I came home picked up a few solutions, these are to be temporary and the hit ware heater needs to be replaced, and added another shutoff value.

All appears to be sealed and working.