How to Properly Flush a Water Heater Safely

Most water heater manufacturers say you should drain the heater each 6-12 months. Even if there’s no obvious problem, it’s recommended because draining it removes dirt, sediment and minerals which can gather inside, especially in the bottom of, the tank. Not draining the tank can lead to an inefficient, more expensive water system.

You could run into some visible, or scented, problems which will cause you to drain a water heater. What are these problems? Then, how do you drain a home water heater safely?

Reasons for Draining a Water Heater

Dirty, Discolored Water

A water heater’s tank is the main water tank for the whole house. It’s not the only one. A toilet, for instance, is also a standing water tank. Contamination in a home’s water, over time, will gather in the main tank.

Your water heater tank is also a water filter. It does a good job for a long time, passing thousands and thousands of gallons through. Over a long period of time, it’s normal for particles, contaminants, minerals, and so on to gather. This can also create corrosion. A water heater should be flushed periodically to stop this problem.

If you’re getting dirty, rust-colored, and smelly water when you didn’t before, it could be rust and corrosion. It could well be sand, clay, and other contaminants. This is more likely in well systems. It may happen following a water main break in a neighborhood or area.

Milky or Cloudy Water

Sometimes, you get milky or cloudy water. This can happen in hot or cold water. It can happen with new or old water heaters. There are some different causes for this.

It’s possible to get extra or an abnormal amount of air in water. This can happen with a faulty faucet aerator, a problem all the way at the public water supply facility, in a good system, or when there’s a big change in the temperature of the water underground.

Draining your water heater may be a possible help to solve this condition or something which is a good idea after the problem is resolved.

Safety Before Beginning

Before beginning, you need to know where your house’s main water shutoff valve is. While you may not need it during this task, it’s important to know where it is and how to shut it off while working on any plumbing matter. This is a good idea for home or property owners in general.

Draining a water heater means working with water that may be very hot. You need to take all safety precautions. You should turn off the water heater a few hours before you start. Let the tank cool down. If you can’t do this, you can wear heavy-duty rubber work gloves and safety glasses.

Steps to Drain a Water Heater Safely

• Do an Initial Flush

Before turning off the water, attach a yard hose to the drain valve. Run the hose to the outside or into a bucket if possible. Try to flush the tank out while you still have water pressure. Open up the valve for a few seconds, then close it. The pressure should remove sediment in the valve itself. If there’s a lot of debris, you might try this two or three times. This will help in draining the tank later.

• Turn Off the Water Heater

Turn off the gas or electricity to your water heater. Now shut off the water, using either the shutoff valve in the cold-water pipe above the water heater or the main water supply valve to the house. Check to see if the water is off by checking the hot water faucet in the house. Water might come out, in a burst, at first, but should slow to a trickle or drip if the water is off. Leave a hot water tap open in a sink so pressure doesn’t build in the tank.

• Open the Drain Valve

With the hose connected, open the drain valve. You may be able to do this by hand. If not, you can use a flat-head screwdriver.

With the valve open, water will run out of the drain, through the hose. Close the valve when you need to empty a bucket or stop the flow. Repeat opening the valve until the tank is empty.

• Flush the Tank

Once the tank is empty, you want to flush it with water, a few gallons at a time. Turn the water on for a few seconds at a time. Let it drain completely each time. You’re looking for the water flowing out to become clear.

• Refill the Tank

Now you’re putting everything back together again. Close the drain valve. Disconnect the garden hose. Make sure you have all but one hot water faucet in your home turned off. Turn the water on. Go check the one tap you left open. Once you’re getting clear water there, it’s fine, turn the tap off.

• Relight the Water Heater

Relight the water heater pilot, or turn the power back on if it is an electric heating system. Within about an hour, you should have hot water.

• Double Check the Drain Valve

See if your water heater drain valve is entirely closed by checking for leakages at the spout. If it did not close entirely, you can put a threaded hose cap over the hose thread at the outlet. You may need to replace the valve.

South End Plumbing specializes in leak repairs and water heater installation, so remember, we are just a click away. We also specialize in tankless water heaters – give us a call! South End Plumbing is one of the only companies that will give you a free estimate. Call us at 704-919-1722 or fill out the form online to schedule a visit.