Water – Are the cold and hot water circuits typically isolated in residential plumbing

water-heater

I have a shutoff valve on the cold side of the water heater inlet. I also have a water main shutoff valve coming from my well. Are the cold and hot water lines in the house independent of each other and can I leave the main water valve open and just shut off the valve on the inlet side of the tank, therefore allowing me to drain the tank while still having water to the cold side of the house?

Best Answer

Yes, you can leave the main on. Just shut off the inlet to the water heater. Your hot taps at the sinks won't work of course (the cold will), but then you can drain the tank. If the tank has some age on it, expect it to take a while too, lime often builds up and clogs the drain outlet.