A water heater usually makes unusual noises because of sediment buildup at the bottom of the tank, water hammer in the pipes, a heating element that is failing, pressure that is too high, or a relief valve releasing water. The type of sound can help you figure out which one is happening.
Popping or Rumbling
This is the most common noise. Minerals in the water settle at the bottom of the tank as sediment. When the burner or lower element heats the water, small pockets of water trapped under the sediment boil and pop. Sediment also makes the heater work harder and can shorten its life. Flushing the tank can help if the buildup is not severe.
Crackling or Sizzling
On electric heaters, sediment can cover the lower heating element and make a sizzling sound. On gas heaters, a sizzle may come from condensation dripping onto the burner. If you see water dripping near the burner, have it checked for leaks.
Banging in the Pipes
A loud bang when a faucet shuts off quickly is often water hammer. The sudden stop of moving water makes the pipes jump. It can loosen fittings over time and may point to high water pressure.
Hissing or Screeching
A screeching sound can come from a partly closed valve that restricts flow. Hissing near the top of the tank may come from the relief valve releasing water or steam, which can mean the heater is overheating. Turn the heater off and keep people away until it is checked.
Sounds that get louder over time, or that come with leaks or rusty water, often mean the heater is wearing out.
If your heater is making new or loud noises, it can be inspected, flushed, or repaired. Noises are also a reminder that yearly water heater upkeep, like flushing sediment, can extend its life. Call JPR Plumbing at (833) 603-1840.