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How to Flush Sediment Out of Your Water Heater Tank

Did you know that part of maintaining a water heater requires flushing its tank? If not, you may be wondering what’s involved in the process. Discover the steps of how to flush your water heater’s tank in a safe way. Also, find out some of the benefits of this maintenance task.

Materials Needed to Flush Your Water Heater Tank

You probably already have many of the materials necessary to flush your water heater. These materials include:

  • A bucket
  • A rubber hose
  • Work gloves

Step One: Turn Off the Power

The first step in the process of flushing your water heater is one of the most important. If your water heater operates on gas, turn its gauge to the pilot setting. If you have an electric water heater, shut off the electrical power to it. You do this by shutting off the appropriate circuit breaker in your breaker box. Shutting off the power to your water heater is a necessary safety precaution for this project.

Step Two: Turn on a Hot Water Faucet in Your Home

Turn on the hot water faucet in your bathroom sink. Turning on the hot water helps to remove the air bubbles from your water heater tank. This simple step can help it to fully drain. After a minute or so, turn the faucet off.

Step Three: Shut Off the Cold-Water Valve

The cold-water valve on a water heater is usually located at the top of the unit. It may have a label or even a blue handle designating it as the cold-water supply. Turn the valve to the off position.

Step Four: Secure a Hose to the Water Heater

The next step is to locate the spigot on your water heater and attach your hose to it. This spigot looks like one you’d find attached to an exterior wall of a home. You can use a traditional garden hose or invest in a shorter rubber hose, so you don’t have so much slack to deal with. Next, put the end of a hose in a bucket so your water can drain into it.

If your water heater sits on a shelf several feet above the floor, gravity is going to help the water drain out. Alternatively, if your water heater sits on the floor in a basement or elsewhere, it may not be so quick to drain. Some water heaters require a pump to drain them.

Once you attach the hose, several drips of water may come out of the spigot right away. So, it’s best to have the end of the hose inside your bucket before attaching the other end to the spigot.

Step Five: Begin Draining the Water Heater’s Tank

After attaching your hose to the spigot, turn the lever above it to open the valve. Make sure the bucket is secure on the floor, so it doesn’t fall over as the water goes into it.

Look at the water coming out. Is it mostly clear? If so, that’s a good sign. It means there’s not much sediment lingering in your water heater’s tank. However, if you see dark water with lots of sediment, your water heater may be having issues. If this is the case, it’s best to get the condition of your water heater evaluated by a qualified plumber. After draining all of the water out of your water heater tank, shut off the valve.

Step Six: Flush Out the System

Now, it’s time to flush the system with cold water. Reach up to turn on the cold-water valve. Cold water will move through the system loosening the remaining sediment. This part of the process is effective at loosening sediment on the bottom of the tank.

Take five minutes or so to flush your water heater tank with cold water. Then, turn off the cold-water valve and open the valve attached to your hose. Of course, check to see if the end of your hose is still in the bucket.

Is there still a lot of sediment in the water coming out of your tank? If so, you may need to repeat the process of flushing and draining the tank.

Detach the Hose and Turn On the Water Heater

After you finish draining your water heater tank for the last time, close the valve. Then, unhook the hose attached to the spigot. After turning on the cold-water valve, run the bathroom faucet again. Finally, turn on the gas or electrical power to your water heater. Watch your drain valve for a few minutes to ensure there are no drips.

Why Is It Necessary to Flush a Water Heater?

Seeing all of that sediment coming out of your tank is an illustration of the importance of flushing your water heater. When you start to accumulate layers of sediment in your tank, this debris prevents your water heater from working efficiently. Over time, layers of sediment can damage the structure of your water heater requiring you to replace it.

Some of the ways you can benefit from regularly flushing your water heater include:

  • Prolongs its life
  • Heats water more quickly
  • Reduces noise of the appliance

How Often Does It Need Flushing?

Generally, a water heater tank should be flushed once a year, but some water heater tanks need flushing more often than others. One way to determine how often to flush your water heater tank is to observe the amount of sediment coming out. If you have a lot of sediment appearing every time you flush the system, then you may need to flush it more often than once per year. Calling in a qualified plumber to evaluate your water heater is another way to determine how often it should be flushed.

Is It Necessary to Flush a Tankless Water Heater?

Yes. Though by definition, a tankless water heater has no tank, the system does need flushing.

Flushing a tankless water heater is a little more complicated than flushing a tank water heater. Specifically, you need to use a pump as part of the process. If you don’t feel confident about flushing your own water heater, it’s a good idea to call in the professionals.

Providing expert water heater maintenance is something we’ve been doing at TR Miller Heating, Cooling & Plumbing in Plainfield since 2008. Our plumbers have experience tending to both tank and tankless water heaters. We use the latest equipment to flush your water heater tank in a safe and efficient way. We dispose of the messy water and handle every step in the process, so you don’t have to!

Our family-owned company provides water heater repair and replacement along with toilet repairs, drain cleaning, and sewer line repair. We offer heating and cooling repairs and installation work as well. Contact TR Miller Heating, Cooling & Plumbing in Plainfield to schedule an appointment today!