Pressing Buttons

This morning I got up to the exciting news that there was no hot water in the house. Nice. The kids had to go to school after a brief and brisk shower. I went to the basement and drained the hot water tank (with Lucie manning the other end of the drain hose). Turned off the breaker and then turned it back on. Nothing. I found some panels on the tank so I unscrewed them and found a reset button. It was popped so I pressed it and all seems to be good now. Makes me wonder what made it pop in the first place but that is what they installed it for I suppose. The best news is, now I get a hot shower...