I am having an issue with my shower. Every so often the water is not hot. It is luke warm and then goes cold after running it a while. When this happens the water in the rest of my house is also luke warm. After running the luke warm water until it goes cold and waiting for a while the water heats up to the normal temperature. I have an electric water heater that was just replaced last year. The problem seems random. Sometimes I will go a month or month and a half with it not happening and then sometimes it will happen up to three times a week. Any help or insight would be greatly appreciated!