We’d wager that you don’t like spending money on home repairs. Sure, cosmetic fixes can be fun, but things like pest control, plumbing repairs, and getting a new furnace aren’t so exciting.

If you want to put off paying for a new water heater as long as possible (and we don’t blame you!), then you need to flush your tank-style water heater once a year. It’s an often-overlooked task, but it’s a very important one. If the sediment in your water heater accumulates too much, it can reduce your water heater’s efficiency and cause damage.

Use this step-by-step guide to learn how to flush a water heater so you can save money and prolong the life of your water heater.

Step 1: Turn Off the Thermostat (If Applicable)

If you have a gas-powered water heater, turn off the thermostat or set it to “pilot.” Older models will require you to re-light the pilot light when you turn it back on after the project is complete.

If you have an electric water heater, you can disregard this step and proceed to step 2.

Step 2: Shut Off the Power Source

You’ll need to turn off the power source to avoid damaging the water heater. For gas water heaters, find the gas pipe that leads to your thermostat and turn the valve off. If you have an electric water heater, go to your main breaker box and turn off the switch that powers your water heater.

  • 💡 Pro Tip: Try to tackle this task first thing in the morning. You can power off the water heater the night before to allow the water inside the tank to cool before working on this project.

Step 3: Let Hot Water Run From a Faucet

how to flush a water heater running water faucet

If you want to be extra careful to prevent burning yourself with hot water, you can turn on the hot water on one of your nearby faucets. This can be a sink or your bathtub. Let it run for the entire flushing process to help prevent a vacuum from forming in the supply lines.

Step 4: Close the Water Supply

There should be a cold water supply pipe that leads to the top of your tank. You can find the supply valve near the top of your hot water heater. Turn the valve to the off position.

Step 5: Secure a Garden Hose to the Drain Valve

There should be a drain valve at the bottom of the water heater that looks like a regular outdoor faucet. It may be made of plastic and could be hidden under a removable cover. Once you locate it, securely attach a garden hose to this valve with a pair of pliers.

Extend the other end of the hose to an area where you can drain out the water. Ideally, this is outside, but it should at least lead to a large bucket.

Step 6: Turn on the Drain Valve to Start Draining

Place a towel over the drain valve and hose connection to protect yourself from any hot water that may spray from the connection point. Open the drain valve to begin drawing water out of the tank.

If you can locate the pressure-relief valve at the top of the water heater, you can very carefully open it to improve the flow of water.

  • Keep in mind that if you didn’t allow the water to cool down the night before, then the water will be extremely hot. Use the utmost caution to avoid touching the water or steam. Gloves and protective eyewear can be quite helpful.

Step 7: Confirm the Water Is Sediment-Free

how to flush a water heater checking for sediment

Let the water drain for about 15-20 minutes. Then, fill up a bucket (or separate bucket) with the draining water. Let the water sit for a minute or two, then check to see if it’s fully clear.

If there’s still sediment in the bottom of the bucket or the water is cloudy, then you’ll need to keep draining your water heater for at least another 10 minutes. Once the water runs clear, then you can move on.

Step 8: Close the Drain Valve and Remove the Hose

Turn off the drain valve and detach the hose. Point the end of the hose upwards until you get outside to avoid spilling hot water on yourself. Keep the pressure-relief valve open, and let the water running from your nearby faucet continue to run.

Step 9: Re-Open the Water Supply Valve

When your garden hose is safely outside, you can return to your water heater. Open the water supply valve again to let the tank fill back up. (Still keep that pressure-relief value and nearby faucet open! This helps bleed air out of the water line.)

Step 10: Turn the Power Back On Once the Tank Is Full

When your tank is completely full again, you can proceed with turning the power source back on. (The water running from your nearby faucet will start to run at full pressure when the tank is full.)

For electric water heaters, turn the power switch back on. For gas or propane water heaters, turn the gas valve to the on position and turn the thermostat back to the original setting. You may need to re-light your pilot light depending on the model of your water heater.

Now, you can finally turn off the nearby faucet and close the pressure-relief valve. Wait a half hour to allow the water to heat back up— then you should be good to go!

Not Feeling Up to It? Paladin Plumbing Can Help!

Be sure to mark your calendar so you don’t forget to complete this task each year. But if you’re not feeling confident after reading this guide, that’s okay! Many homeowners prefer to leave larger tasks like this in the hands of a trained professional.

Paladin Plumbing is an expert in all things water heaters. Get in touch today to schedule any plumbing maintenance you need!

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