Flush water heater

Why It Matters

Sediment settles to the bottom of the tank, insulating the heating element and reducing efficiency. Heavy sediment shortens tank life by years.

Tools

• Garden hose
• Flathead screwdriver or slot driver (for drain valve cap)

How to Do It

1. Turn off the water heater: switch the breaker to OFF for electric units, or set the gas valve to the pilot position for gas units.
2. Connect a garden hose to the drain valve near the base of the tank and run the other end to a floor drain, utility sink, or outdoors.
3. Turn off the cold-water supply to the tank, then open a hot-water faucet somewhere in the house to prevent a vacuum from forming.
4. Open the drain valve and let the tank empty. Sediment-heavy water will run out first; wait until the water runs clear.
5. Close the drain valve, disconnect the hose, and turn the cold-water supply back on. Let the tank fill completely before restoring power to electric units. Gas units can be relit once the tank is full.

Related Tasks

• Clean tankless water heater inlet filter Once a year
• Flush and descale tankless water heater Once a year
• Lift and release water heater pressure relief valve Once a year
• Replace water heater anode rod Every 5 years