Flush your water heater

Steps

1. Switch the heater to pilot/vacation, or turn its breaker off on an electric unit, and let the water cool.
2. Close the cold supply valve on top of the tank.
3. Attach a garden hose to the drain valve and run it to a floor drain or outside, downhill.
4. Open the drain valve and a hot tap upstairs to break the vacuum; let the tank empty and run until clear.
5. Close the drain, reopen the cold supply, let the tank fill fully, then restore power or gas.

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