How to Drain Your Water Heater: A Step-by-Step Guide 

Tank water heaters are a dependable way to provide a fast supply of hot water for your home. The presence of a storage tank ensures some hot water is always available. But over time, foreign substances may accumulate within the storage tank. This might be sediment or mineral buildup arriving from the main water line or a crack in the pipes. Whatever the source is, this buildup can negatively impact the efficiency of water heaters. In severe cases it can clog up drainage and might even cause premature failure.

Fortunately, draining your water heater and clearing out sediment buildup is a relatively simple task. An experienced plumber in the U.S. can handle the process, but you can also drain the tank yourself if you know what you’re doing. Whatever you choose, draining the tank now can help minimize the risk you’ll need premature water heater replacement.

Before You Begin…

Before you start draining the tank, you should shut off the cold water supply. The supply valve connects your water heater with the main water line. Unless you have access to a well (and you may need to drain the tank more frequently if you do), the water main provides all the potable water your home uses. Keeping the valve sealed will prevent more water from flowing into the tank, allowing you to completely drain it.

You’ll also want to grab a rubber hose, like one you can use for yard work. The hose allows you to safely drain the water heater tank without spilling water all over your garage, utility closet, attic or wherever the water heater is kept. Make sure you leave the other end of the hose far away from your home to keep the water from seeping back inside.

Finally, a screwdriver can help you loosen stubborn screws or valves. You shouldn’t need any more tools than this unless you come across a problem with the water heater or adjacent piping. At that point, it might be best to call a certified plumber in the U.S..

Step 1: Shut Off the Water Heater

After you’ve turned off the water supply, you can shut off the water heater itself. This will be on the thermostat for natural gas water heaters or through a breaker switch for electric models. The pilot setting on gas water heaters can remain on during flushing, but electric models must be completely off. This is because of the heating elements electric water heaters have, which remain submerged. In a drained tank, they can quickly overheat. You should also check the model’s manual, as some water heaters need to be completely full before the heating elements are turned on.

Even after you’ve shut off the water heater, you’ll have to wait for the water stored in the tank to cool down. It could be hours before the water cools to a safe temperature, so it is usually best to leave the rest of the process for the following day.

Step 2: Secure the Hose to the Water Heater’s Drain Valve

Tank water heaters are designed with a drain valve you can use to empty the storage tank. Once you’re confident the water supply is disconnected and the water heater itself is off, locate the drain valve. Some models may have it covered up. Make sure the hose is firmly attached to prevent spilling hot water near you and the water heater.

Step 3: Open a Faucet or Other Hot Water Tap

Your home’s plumbing takes advantage of pressure within the piping to maintain a consistent flow of water from the main water line to the rest of the house. This pressure needs to be relieved before the hot water can actually drain out of the tank. By heading to the nearest faucet or spigot, you’ll alleviate the pressure inside the piping. All you have to do is open the hot water tap to relieve the pressure before heading back to the water heater.

Step 4: Release the Drain Valve

Remember that this water could still have some residual heat. Open the drain valve and allow all the water to drain from the tank. This should pull sediment buildup out of the tank and away from your home. But some buildup might be stuck to the inside of the tank. Turning the cold water supply back on will help wash away stubborn minerals and other substances from the tank.

Keep repeating this step until the water appears free of sediment or minerals. If the drain isn’t working because of a clog, a trained plumber is likely required.

Step 5: Re-Shut the Valve Before Refilling the Water Heater

If everything proceeds like it’s supposed to, you should be able to remove most excess sediment stuck inside your water heater. Close the drain valve, disconnect the hose and open the water supply to get things working again. As the water heater tank begins to fill, return to the hot water tap you opened. Once cold water starts to flow, you know the pressure is back where it needs to be.

At this point, you can open the gas valve or flip the breaker switch back on. Like we mentioned before, don’t forget that certain models might need to be completely full before the water can be safely heated. Make sure you review your manufacturer’s instructions before starting the process.

Keep Your Water Heater Sediment-Free for Best Results

Tank water heaters are still a great option for supplying your hot water needs. Draining the tank every 1-2 years will help remove sediment buildup and keep things running at maximum efficiency. If you think your water heater is past the point of efficient heating, consider looking for water heater replacement in the U.S. from a technician you trust.