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How Do I Flush My Water Heater’s Tank?

Taking a long, hot shower after a hard day of work is one of life’s finest luxuries. However, have you ever stopped to consider where it’s coming from? The hot water tank is an essential piece of your home’s plumbing system, but it can fall into malfunction over time. Performing routine maintenance like flushing the water tank is important in order to get the most out of it. Fortunately, water heaters are relatively easy to care for as far as household appliances go. That means flushing the tank a task that many homeowners can comfortably do on their own. This guide will provide you with a step-by-step checklist for how to flush the water tank.

Why You Should Flush Your Water Tank

Flushing the water tank yields a variety of benefits for everything from the tank itself to your pocketbook. As minerals collect inside the tank, they gradually decrease the system’s performance and lifespan. Gas-powered units may experience uneven heating that can lead to cracks forming along the wall of the tank. For electric heaters, the lower heating element may burn out as sediment accumulates along the bottom of the tank. Both types of heaters may develop clogged drain valves as a direct result of mineralization.

Letting the sediment sit for a long period of time will allow it to calcify and harden, making it extremely difficult to remove. If the problem gets bad enough, you may have to have the entire unit replaced. Luckily, you can prevent these problems and more by periodically flushing the tank. If you notice your water heater making popping or rumbling sounds, then your tank is most likely suffering from some serious mineral build-up. This telltale sound is produced by gas bubbles struggling to rise through the layer of gunk. These bubbles can create something called “hot pockets” inside gas-powered units, which can eventually cause serious damage or even premature failure.

When Should My Water Tank Be Flushed?

Plumbers recommend flushing the water tank once per year. If you live in an area with hard water, you may need to do it more often. There are a few signs to look out for when your water heater is ready to be flushed. The one homeowners usually notice most often is that they’re getting less and less hot water from the tank before it runs out. If you’ve noticed a gradual drop in hot water quantity, there’s a good chance that mineral build-up is to blame. The second sign requires a bit of investigation work. You’ll need to take a closer look at the water coming out of the tank’s drain valve. If it’s cloudy or white, that means it contains a high level of sediment.

If you haven’t had your water heater flushed in years, it’s best to leave the job to a licensed plumber. This is because sediment can create small cracks along the bottom of the water tank. You won’t notice any water leaking out as long as the sediment remains in place, but once it’s removed via flushing, those cracks will open up and are free to leak water. A leaky water heater can be a crisis situation for a homeowner on their own, but a plumber can patch up the problem before serious damage occurs.

If you do decide to flush your water heater’s tank on your own, we recommend following these steps:

1. Turn Off the Water Supply

Before you start tinkering with the machine, you’ll want to make sure it’s not actively receiving water. You can do this by turning off the cold-water supply valve located on top of the heater. If you live in an older home, you may have to do this by turning off the water where the main supply line enters your house. Once this is done, you have one more step: powering down the unit. To turn off an electrically powered unit, you need to flip the switch on your home’s circuit breaker. For a gas-powered unit, you’ll have to locate the thermostat and switch it to “pilot” mode. Give the unit a while to cool down before you start handling it to minimize the chances of being burned.

2. Attach a Garden Hose to the Drain Valve

Now it’s time to grab a clean garden hose. A ton of water is going to flow out via the hose, so you’ll want to place one end in a floor drain or outdoors if it reaches. Once your hose is in position, attach the receiving end to the drain valve located at the bottom of the water heater.

3. Open the Drain Valve

This step has two parts. First, you’ll need to open a nearby hot water tap to help the tank drain faster. Next, you need to open the drain valve to allow the water to flow from the tank. Keep in mind that this step requires some patience since most hot water tanks hold between forty and sixty gallons. Sediment build-up can slow this process down even further, so be prepared to wait a bit.

4. Turn the Water Supply Back On

Once the tank is fully emptied, it’s time to flush it. You can accomplish this by keeping the drain valve open and turning the cold water back valve back on. As the cold water filters through the tank, it will remove any leftover sediment. Keep repeating this step until the water running out of the garden hose is clean and clear.

5. Close the Valve and Restore the Heat

After the tank has been fully flushed, you should close the drain valve, remove the garden hose and turn off the hot water tap. Next, power the unit back on. For gas heaters, you’ll have to turn the natural gas valve back on. Electrical units can be powered up by flipping the circuit breaker back into the “on” position. After everything is up and running again, be sure to check for leaks and tighten the valve if needed.

What About Tankless Water Heaters?

Despite not having water tanks, tankless water heaters can also suffer from mineral build-up and scaling. Due to their unique architecture, the process of flushing a tankless water heater is totally unlike flushing a traditional unit. Most hardware stores carry tankless water heater flush kits that are relatively easy to use.

Quality Water Heater Services

Although flushing a water heater is relatively simple, not all homeowners are comfortable doing it on their own, and that’s okay. Landry Mechanical Inc Plumbing HVAC & Electric has a team of licensed plumbers who would be more than happy to provide expert maintenance. We’ve been in business since 2008 and are proud to have earned an A+ rating from the Better Business Bureau. In addition to water heater service, we also provide a range of plumbing solutions like drain cleaning and plumbing repair as well as electrical services. Visit our website to learn more about financing and our partner plan!

Give Landry Mechanical Inc Plumbing HVAC & Electric a call to schedule water heater maintenance in Worcester County or learn about our additional service offerings!

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