How do you tell if you've melted the heating coil in an electric water heater? So after checking that there was running water, I turned on a hot water heater by flipping the fuse in the fuse-box. Came back to the house later and tested the water, it was hot. Took a shower, ran out of water near the end... read that no water in the heater can cause the coil to melt. So... within 30 minutes, maybe an hour. I turned off the water heater fuse. I then turned on the fuse to the well pump that I hadn't turned on before. (Which is likely why I ran out of water in the house.) I checked hours later and there was running water again. I left the heater fuse off. Did I melt the water heater coil? Is that expensive?