How to Troubleshoot a Water Heater
Rumbling or Pounding:
If you hear a rumbling and pounding noise coming from your water heater, it might be related to the formation of scale and sediment in the appliance. Scale can form on the inner tank, which traps a small amount of moisture. This, in turn, gets turned into steam and builds pressure, causing the rumbling and pounding noises. These sediment and scale deposits can shorten the life of your water heater. If enough sediment accumulates, it can cause the drain valve to clog; this is true for gas and electric heaters. Flushing the water heater once a year can help remove the sediment that builds up.
Sizzling or Pinging:
After heavy usage of hot water, there might be a sizzling or pinging noise that comes from your water heater. Due to the condensation that builds, drops of water can fall on the burners, causing the sizzling or pinging noise. If you open the jacket door to see the burner assembly, you might be able to see the watering dropping and causing the noise. The noise should stop once the heater is hot, but if it continues, you may have a leak in the connection.