How to Clean an A.O. Smith Electric Water Heater

Flushing the Tank

1. Your AO Smith electric water heater will need to be disconnected from the power source before you clean the interior of the tank. Flip the breaker, and unplug the heater. Shut off the water using the water shutoff that is generally located above the water heater.

2. Along the bottom of the tank, the water heater has come equipped with a threaded flush valve with a handle that turns. Connect one end of the garden hose to this flush valve, and run the garden hose to a place outdoors where the heater can drain.

3. Turn the valve to open, and allow the full contents of the water heater to drain into the hose and outdoors. Turn the flush valve off.

4. Open the water valve at the top of the heater, and allow the tank to fill with water for 2 to 3 minutes before again cutting the water supply.

5. Again turn the flush valve on, and allow water to flow outside until the tank is empty. These steps should be repeated until the water running outside is free of discoloration and mineral buildup.

Resources

• AO Smith

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Tips

Commercial tank additives are available that claim to clean the water tank of debris. Check with your water heater's warranty before using these additives. If the flush valve gets clogged, it is generally due to mineral buildup in the valve itself. Gently clear the valve with a screwdriver.

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Warnings

Water that flows from the heater is hot. Drain in a safe place away from materials that will be harmed with the hot runoff. Children should be kept away from the drainage area.

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