How Often Should You Drain Your Water Heater?

One key task homeowners often overlook is draining and flushing the water heater. This process is relatively straightforward, but it’s essential to the ongoing functionality of the appliance. Depending on the age of the water heater and the quality of the water, you should typically drain the water heater about once every six months to once a year.

Generally, if you have a water heater that is approaching the end of its lifespan or you live in an area with hard water where the mineral content tends to be higher, then you should aim to drain the water heater every six months to ensure optimal operating efficiency.

Why Do I Need to Drain My Water Heater?

Draining the water heater is a necessary part of maintaining these essential home appliances.

“Over time, sediment accumulates at the bottom of the tank,” says Josh Mitchell, Plumbing Technician and Owner of PlumbingLab.com. “This buildup can reduce heating efficiency, shorten the water heater’s lifespan, and increase energy bills. It can even cause rumbling or popping sounds as the sediment traps water and creates steam pockets.”

To keep the water heater in good condition, it’s important to drain and flush the tank about once every six months to once a year. Otherwise, the water heater may cost you more on your energy bills as it attempts to heat the water through a coating of sediment. If you neglect this job for too long, it could even lead to the water heater failing entirely.

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4 Signs the Water Heater Needs to be Drained

If you aren’t sure whether the water heater needs to be drained immediately or if you still have some time before you need to drain and flush the tank, there are a few signs to watch out for that indicate you may have left this job for a bit too long.

• Bad smells coming from your hot water can point to bacteria living in the water heater. Typically, turning up the temperature in the water heater to about 140 degrees Fahrenheit for eight hours will kill the bacteria, then you can flush the tank to get rid of the contaminants.
• No hot water or lukewarm water from the water heater can be a sign that sediment inside the water heater has built up on and around the heating elements, preventing the water heater from operating properly. Drain and flush the water heater to get rid of the sediment in the tank and restore the hot water.
• Strange sounds emanating from the water heaterlike rumbling or popping, often indicate that there is sediment inside the tank. By draining and flushing the tank, you should be able to stop the water heater from making these odd noises.
• Rust-colored hot water is a clear sign that mineral deposits are building up inside the water heater and corroding the tank. This means that you need to drain and flush the water heater, but you may also need to have the anode rod replaced to prevent further tank corrosion.

How to Drain a Water Heater

Draining a water heater is fairly simple, though the process does take several hours to drain the tank, refill the tank, and heat the water, so many DIYers choose to drain and refill the tank later in the day, while allowing the water heater to heat the water overnight.

1. Start by turning off the power and gas supply to the water heater. If you have an electric water heater you only need to turn off the power.
2. Next, close the cold water inlet valve located at the top of the water heater.
3. Locate the drain valve at the bottom of the water heater, then attach a garden hose and run the hose to a suitable drainage location, like a nearby laundry sink or even outdoors.
4. Open a hot water faucet in the home to relieve the pressure on the system, then open the drain valve to drain the water heater.
5. After the tank is fully drained, turn the cold water supply back on to flush any remaining sediment, then close the drain valve and remove the hose.
6. Let the water heater refill before turning the gas and electricity back on, otherwise you may burn out the heating element.

What Happens If I Don’t Drain My Water Heater?

Draining the water heater is essential to the heating efficiency and functionality of the appliance.

“Neglecting this task can lead to sediment buildup that eventually corrodes the tank, causing leaks or even a complete failure,” Mitchell says. “On average, draining your heater can extend its life by three to five years.”

Also, if the tank is not regularly drained and flush, the build up of minerals can prevent the water heater from heating the water properly, leaving you without a readily available hot water source.

Best Time of Year to Drain a Water Heater

While you can usually drain the water heater at any time throughout the year as long as you have an appropriate drainage location, it’s typically best to drain the water heater during the spring or fall.

“These seasons typically have moderate water usage,” Mitchell says. “You’ll avoid potential issues during the peak demand of winter or summer.”