How to Flush a Water Heater and Extend its Lifespan

Replacing major systems like a water heater can be expensive. Luckily, if you regularly drain your water heater to remove sediment, it may add years to the system’s longevity and prevent you from having to fix a broken water heater. Here are some simple steps for how to flush a water heater. 

You never realize how much you rely on your hot water heater until it breaks down. A broken hot water heater means no hot showers, no washing dishes, no laundry—and it can also mean shelling out several hundred dollars if you don’t have a home warranty that includes coverage for water heaters. 

What Are the Benefits of Draining or Flushing a Hot Water Heater? 

It should come as no surprise to you that a lot of water travels through your water heater—and that water is full of minerals that can build up in the tank in the form of sediment. Sediment creates hot spots inside the heater that can shorten its life by damaging the tank. If you have an electric heater, sediment in the hot water heater can accumulate on the heating element, causing it to fail and necessitating an expensive repair. 

Are you hearing popping, banging, or rumbling noises from your water heater? That’s the sound of water percolating through the sediment inside the tank. If you’re hearing banging or rumbling noises, you probably need to clean the water heater, especially if you haven’t done so in more than a year. 

Draining your water heater regularly can help boost the efficiency of the appliance and save it from unnecessary wear and tear. It will also save you money, because you’ll get more use out of it before it needs replaced. The more often you drain or flush your hot water heater, the less sediment you’ll have to deal with, and the less likely it will be for it to clog up your water heater’s drain.  

How to Flush a Water Heater 

Draining your water heater is a simple maintenance procedure that you should be able to do on your own. Here’s how to drain your water heater, step by step: 

1. Turn off the thermostat. 

Whether it’s gas or electric, your water heater should have a thermostat knob, usually near the bottom. Turn off the thermostat. If you have a gas appliance, this will turn off the pilot light, which you’ll need to relight after flushing the tank. 

2. Turn off gas or breaker. 

If you’re draining a gas water heater, turn off the gas. If you’re draining an electric water heater, go to the fuse box and turn off the breaker that controls the hot water heater. Then turn off the cold water supply to the water heater.  

3. Open hot water tap in home. 

Open a hot water tap in your home. Keep it open until you’re done flushing the water heater tank. This will keep a vacuum from forming so you can perform the maintenance more easily. 

4. Open the pressure release valve. 

Open the water heater’s pressure release valve. Not only will this help the tank drain faster, but it’s also an important part of water heater cleaning because it lets you test the pressure release valve. You want to make sure the pressure release valve is working properly—if it isn’t and too much pressure builds up inside your water heater, it could burst. 

5. Connect a hose to drain line. 

Connect a water heater drain hose—a simple garden hose will also do the trick—to your water heater’s drain line. It’s the thing that looks like a spigot at the bottom of the tank. Run the hose to your basement drain, or if you don’t have one, run it outside the house. 

6. Open spigot on drain. 

Open the spigot on that drain and empty your hot water heater completely. If you haven’t drained your water heater in a while, it will be full of sediment. The sediment in a hot water heater can get pretty gnarly, so be prepared for a bunch of goop to come out. Though it usually isn’t harmful, seeing all the sediment that’s been floating around in the water you use to shower and cook with may make you want to flush your water heater more often. Yuck. If your drain valve gets clogged with sediment at any point in the process, you can buy a shop vac attachment for the drain that will help you suck it out. 

7. Turn on cold water and let it run. 

Once you’ve got the spigot open and you’re draining the hot water sediment, turn the cold water supply to the heater back on. Let the water flow through the heater, and out your hose, until you’re seeing only clear water and no more sediment emerging from your water heater. At this point, close the spigot, relight the pilot light or restore power to the heater, and turn your heater’s thermostat back up. Close the hot water tap you opened earlier. 

There you have it. Pretty simple, huh? You should drain or flush your water heater once a year—maybe more if you have hard water. A good rule of thumb is: if it’s a’ banging and a’ clanging, it’s time for a draining. That’s just corny enough for you to remember. 

Maintaining all your appliances can feel overwhelming, but if you stay on schedule and don’t let the problems build up, it doesn’t take much time at all. Take care of your appliances, and they’ll take care of you. American Home Shield makes it even easier. We have three levels of protection, so you can choose the plan that’s right for your home and budget. Shop online for all of our pricing and plans. 

Sick of messy tanks? Click here to find out how to install a tankless water heater. 

AHS assumes no responsibility, and specifically disclaims all liability, for your use of any and all information contained herein.