Changing the hot water heater element is probably faster and easier than you thought, and is only a fraction of what a new water heater costs. The steps required are nearly identical for the flange and screw in models, but screw-in types are more common and will require the use of a special tool called a water heater element wrench.
Turn Off the Power
You should always turn off the power when working on a water heater. Electric units can be shut off at the circuit breaker, while gas models will have a knob or dial. If you are not sure your electric water heater is off, use a multimeter to test the wiring before you begin.
Drain the Tank
Shut off the cold water inlet valve, located on top of the tank. Connect a garden hose to the drain at the bottom of the tank and open the drain valve. You only have to drain the unit to a point below the element, but it is a good idea to completely flush the tank anytime you are making repairs. This helps reduce sedimentary deposits in the tank and helps extend the life off all components. Be sure to turn on the hot water faucet closest to the heater to effectively drain the unit.
Remove the Existing Element
Your water heater may have two elements, an upper one and a lower one. If so, both elements are replaced using the same steps. First, open the access panel and remove the plastic safety cover, if present. Disconnect the wires from the element. Go ahead and disconnect the wires from both elements to save time.
A water heater element wrench, also called an element tool, is a specially designed socket that fits over the hex end of the element and has a hole in the other end that will accept the shaft of a screwdriver. Insert the element tool over the element and turn it counter-clockwise. Elements that have been in place for a long time may be difficult to turn. If so, insert a screwdriver through the hole on the element tool to give yourself more leverage. The element(s) will lift straight out of the unit when they have been unscrewed.
If your water heater uses a flange element, you will need to remove the 4 bolts holding it in place and pull the element straight out.
Install the New Element
When replacing a water heater element, always replace the rubber gasket to prevent leaks. Insert the gasket over the threads of a screw in element, or around the base of a flange element. With the gasket in place, install the new element by reversing the removal process and turning the element in a clockwise direction. Screw the component in finger-tight, and then use your water heater element wrench to tighten it another 1/2 to 1 turn. For flange units, replace the retaining bolts.
Refill the Tank
Turn off the drain valve at the bottom of the tank. Turn on the cold water inlet on top of the tank. If you left a hot water faucet on, you might hear your water heater making noise such as a sputtering noise as the tank fills and air is forced through the pipes. Allow the water to flow until all air has escaped the pipes. Turn off the hot water faucet.
Reconnect and Repower
Reconnect the wires to the new element(s), taking care to connect the correct wires to the same equivalent terminals to avoid shorting the element. Turn the circuit breaker on and inspect the water heater. If there is no indication of leaking, replace the plastic safety cover and close the access panel. Allow water to heat for 1 hour, and then verify that the unit is heating properly. You have successfully completed changing the hot water heater element.
Check out the video below to see how to replace an electric water heater element: