Step 2 · Drain the Water Heater
To access the lower heating element, the tank must be drained. Attach one end of a garden hose to the drain valve located at the bottom of the water heater. Run the other end of the hose to a floor drain, utility sink, or outside to a lower elevation. To prevent a vacuum from forming and to speed up the draining process, go to a sink inside the house and open a hot water faucet fully. Now, return to the water heater and open the drain valve. If it's a plastic valve, you may need a flathead screwdriver to turn it. Be gentle as old plastic valves can be brittle. The tank will now begin to drain. This process can take a significant amount of time, from 30 minutes to over an hour, depending on the tank's capacity.