Why do all 3 pipes..the hot, the cold, and the over flow valve run hot water. I can tell by the touch. the overflow which I'm used to having a free flowing tube attached to a pan is connected to a pipe going through the next apartments water heater. and when he. uses water mine drains/fills up. I guess he did this to save himself money but its costing me a fortune Also there is a knob in the lower part of the wall with just a handle...maybe should be the cold pipe wall entrance? Or is this sounding normal more like just a slipped / broken pipe that is supposed to bring the cold water down to lower chamber?