Water heater mineral sediment builds up over time and can turn into a rock solid mass in the bottom of your water heater (see photo).
Sediment buildup causes many problems in your water heating system. It insulates the bottom of the storage tank and blocks efficient heat exchange. If your water heating system pops and bangs, steam bubbles are forming beneath sediment buildup. You’ll be surprised how rusty, cloudy, dirty the water looks. It needs to be flushed out until you see clean water.