A tube of plastic below the cold port of a water heater carries cold water to the bottom of the tank to be heated and keeps it separated from the already-heated water at the top of the tank.

At left are the bottom ends of a standard dip tube from a "self-flushing" water heater and a curved dip tube -- that permits a more effective flush of the tank by swirling calcium around the bottom and out through a ball valve drain assembly.

At right are an assortment of dip tubes, comprising 3/4-inch, 1-inch and 1 1/2-inch and with integral plastic-lined dielectric nipples.

If you're reading this because you have a disintegrating dip tube, with resulting loss of water heater functionality, we sell standard dip tubes for that problem, as well as curved dip tubes for sediment control. Click on the links, respectively, to learn more.