10 Simple Steps to Properly Flush Your Water Heater

Over time, sediment and mineral deposits build up in the water heater tank, which can cause a wide range of problems, including reduced efficiency, unpleasant odors, and even corrosion. By flushing your water heater, you can prevent these issues and keep your water heater running smoothly. But how do you do this? By following the steps we’re going to share with you today:

Step 1. Gather the Necessary Materials

Before you start, gather the necessary materials and tools to make the process as smooth and efficient as possible. Here’s what you will need:

  • A garden hose
  • A flat-head screwdriver
  • A bucket
  • A pair of gloves
  • A pair of safety goggles
  • A towel or rag

Step 2. Turn Off the Power Supply

Safety is a top priority when working with any electrical appliance. Before you begin flushing your water heater, make sure to turn off the power supply. If you have an electric water heater, disconnect it from the power supply by turning off the circuit breaker. If you have a gas water heater, turn off the gas supply by setting the gas control valve to the “pilot” position.

Step 3. Connect the Garden Hose

Locate the drain valve at the bottom of your water heater tank. Attach one end of the garden hose to the drain valve, ensuring a snug fit, and then place the other end of the hose in a floor drain or outside, where the water can safely drain away without causing damage or flooding.

Step 4. Turn off the Cold Water Supply

To stop the flow of water into the tank, turn off the cold water supply valve, typically located near the top of the water heater. This will prevent new water from entering the tank.

Step 5. Open the Pressure Relief Valve

The pressure relief valve is a safety feature that prevents excess pressure buildup in the water heater tank. Open this valve by lifting the lever or turning the handle counterclockwise. This will allow air to enter the tank and facilitate the draining process. Be cautious, as the water may be hot, and steam may be released.

Step 6. Drain the Tank

Now that everything is in place, open the drain valve using the flat-head screwdriver. The water will begin to flow out of the tank through the garden hose. Allow the tank to drain completely, which can take anywhere from 20 minutes to an hour, depending on the size of your water heater.

Step 7. Flush the Tank

Once the tank is empty, turn the cold water supply valve back on for a few minutes to flush out any remaining sediment. As the water flows into the tank, it will mix with the remaining sediment and drain out through the garden hose. Repeat this process until the water is clear.

Step 8. Close the Valves and Disconnect the Hose

After the water runs clear, close the drain valve and the pressure relief valve. Disconnect the garden hose from the drain valve and allow any remaining water to drain from the hose.

Step 9. Refill the Tank

Turn the cold water supply valve back on to refill the tank. As the tank fills, air may be trapped inside, causing sputtering at the faucets. To remove this trapped air, open a hot water faucet in the house and let it run until the water flows smoothly without any sputtering.

Step 10. Restore Power and Check for Leaks

Once the tank is full, restore power to the water heater by turning the circuit breaker back on for electric heaters or setting the gas control valve to the “on” position for gas heaters. Check the drain valve and pressure relief valve for any leaks. If you notice any leaks, tighten the valves as necessary.


Regularly flushing your water heater is a simple yet vital maintenance task that can save you from costly repairs and extend the lifespan of your appliance. By following these steps, you can easily flush out your water heater and keep it running efficiently for years to come. Remember to always prioritize safety and wear appropriate protective gear while performing this task!

With over two decades of expertise, Professor Plumb is a certified and insured professional providing a range of plumbing and gas services, including new installations and repairs. If you are looking for water heater repair and more in Shelby County, AL, work with us today!

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