Here’s a strange one in my opinion... I recently discovered that I my electric water heater was no longer heating. I changed the elements and thermostat to start it began working for about two months. It stopped working again and due to its age, I decided to just buy another one. I turned off the breaker, turned off the cold water valve, connected the hose, opened the drain faucet, opened the pressure valve and it began draining. I checked and made sure the water heater was empty and it was. By the time I got back home with the new water heater I decided it was too late to attempt the removal and new install. When I woke up today, the water heater was full of water and also had some leakage into the drain pan. My question is, how is this possible if the cold water valve is turned off? Did I miss something?