Fixing the water heater noise such as popping, banging, sizzling, rumbling and high pitch sounds. What causes the noisy water heater, troubleshooting tips and how to avoid the problem.
All water heaters, either electric or gas-powered, made by Rheem, AO Smith, Bradford White, Kenmore, GE or any other manufacturer, will have a problem associated with the noise, such as:
The most common reasons for pounding water heater noise are the mineral buildup at the bottom of the tank and water hammer. Water hammer occurs when water is flowing through the plumbing and stops suddenly. The first signs of this problem are the pounding noise, banging and thumping sounds and vibration coming not from the heating unit but piping. The only fix of the water hammer and pounding noise is to install the water heater arrestor.
Sizzling noise coming from a water heater is the result of the condensate leaking on the hot surface of the gas burner surface. The typical residential model will produce approximately one half-gallon of condensate during the hour of operation. Condensate is the normal occurrence of gas heaters as the flue gases are carrying lots of moisture, so when the condensate is dripping on the hot surface it is normal to hear the sizzling noise.
Electric water heaters are also making the sizzling sound when the heating elements are covered with the limescale so water, being trapped next to the element will boil water to steam. Condensation usually stops when the heater reaches the temperature of 115 F.
Popping sound from the heater is the result of hard water and if it is trapped under the lime deposits. If you treat the water and lower its hardness you will successfully remove the annoying noise. Otherwise, if you don't do the treatment (i.e. deliming or phosphoric acid) and regular flushing/maintenance, the high water temperature will bring even more deposits.
Aluminum hydroxide is another reason for the popping noise. If the water supply has relatively high PH and the heater is equipped with the aluminum anode rod, the chemical reaction will result in the creation of aluminum hydroxide (it looks like the green, blue or gray gel) at the bottom of the tank and on the anode rod. Replacing the aluminum with the magnesium rod with flushing and deliming will solve this problem.
Aluminum hydroxide gel in the heater's tank and mineral build-up are the same reasons for rumbling and crackling noise as seen in the previous problem with the popping noise.
Ticking water heater noise is the result of the pressure fluctuations in the plumbing system when flushing the toilet or using the water fixtures, or due to expanding and contracting against the framing or lose connections. The fluctuation can also be heard as the clicking or tapping noise. The energy efficient models are equipped with the heat traps so when the ball is rattling in the nipple it produces this ticking noise also. If the heat traps are the cause of the noise you can simply remove them without reducing the efficiency significantly.