Why is my water heater making a knocking noise?

Answer by  DrColbath (103)

The knocking noise is most likely due to sediment buildup at the bottom of the tank. When the sediment is heated it releases air bubbles which causes the knocking sound.

Answer by  Steve789 (40)

This could be the anode rod. Replacing this will remove built up particles in the heater. These will knock or pop at times. You should also monthly release the pressure release valve.

Answer by  pardhan (92)

if your water heater is old or has been some time since you have purchased it you will experience a knocking noise do not be alarmed it is perfectly normal

Answer by  anujbatta (7)

water heater is making noise because it might have larger temperature. Some filament must have burnt. Some red light problem be there. Thermoscale must be wrong. Water heater is meant for keeping water hot. The heater should be checked by electrician in order to keep the temperature in proper scale. Noise has to be avoided.