Step 6 · Restore Water and Check for Leaks
Before restoring power, you must refill the tank and check for leaks. First, make sure the drain valve at the bottom of the water heater is fully closed and the garden hose is removed. Go back to the sink where you opened the hot water tap and close it. Return to the water heater and slowly open the cold water supply valve by turning it counter-clockwise. You will hear water rushing into the tank. While it fills, keep your eyes on the new expansion tank connection. Once the tank is full (the rushing sound will stop), thoroughly dry the connection with a paper towel and watch closely for any sign of moisture or dripping. If a leak appears, turn off the water and tighten the connection another quarter-turn.