• Turn off the water supply valve on the water heater or close main
  water shutoff valve.
• For a gas water heater, turn off the gas shutoff valve on the unit.
• For an electric water heater, turn off power at service panel; 
  then unplug the unit if it is not directly connected 
  to your home's wiring.
• Water will continue to run out until the water heater is empty.

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