We recently bought a house and I decided that I was going to flush the water heater. I turned off the cold water supply line to the water heater. I then went to open a hot water faucet in the house - but the water kept running! It doesn't turn hot. It doesn't run with full force, but the water keeps running. Therefore, I guess there must be a connection somewhere between the hot and cold circuits. Is this normal? Why would anyone do such a thing? Thanks.