How to flush your water heater. (And if not!)

This can help keep your water heater in tip-top shape for years to come and prevent a costly disaster that requires a late night or weekend call to a local plumber.

Water heaters are one of the most important appliances in your home. It’s a big investment and most of our customers want to make sure they protect their investment for as long as possible. ‍

Annual maintenance of a water heater by flushing will extend its lifespan. This can help keep your water heater in tip-top shape for years to come and prevent a costly disaster that requires a late night or weekend call to a local plumber.

Why Should I Flush my Water Heater?

An easy DIY project, flushing your water heater removes harmful deposits that can build up at the bottom of the tank after prolonged use — and it’s a task many, many homeowners don’t even know they should be considering . Deposits can block or clog your water heater’s pressure relief valve and cause your water heater to lose efficiency. If the pressure relief valve sticks, it will no longer function as a safe pressure relief outlet and the safety of the hot water tank is compromised.

Sediment can also make your water heater less efficient by reducing its hot water output over time, making it less energy efficient and costing you money. The sediment settles at the bottom of the tank and interferes with the heating system, making it unable to heat efficiently. This is especially true if you have hard water in your home – hard water contains a higher percentage of minerals and scale, which can then become sediment in your hot water tank.

Deposits that build up in your tank. (Don’t worry! It’s not coming out of your taps.)

If neither you nor a professional have drained your water in the last five years, Water Heaters Now recommends that you do not flush it yourself. Flushing a water heater that already has a significant buildup of scale can actually lead to more problems. Excessive or large chunks of sediment can get stuck in the tank drain valve or leak out of the water heater and through the pipes in your home — neither of which is an easy fix. When the water heater has not been flushed for a long time, replacement is often required when there is no other maintenance solution. If your water heater hasn’t been flushed in a while, give us a call at (540) 501-6327 and we’ll be happy to look around and give you the best next steps to get your water heater back up and running in optimal condition.‍

If you’re ready to tackle this project yourself, here’s a step-by-step guide to help you flush your water heater.

How to Flush your Water Heater

‍Step 1: Turn off the gas or electricity‍

If you have a gas water heater, turn the gas valve to the off position. You can also shut off the gas supply to the device using the gas shut-off valve.

If your water heater is electric, turn off power to the water heater at the circuit breaker. You must turn off an electric water heater completely before flushing it or you risk burning out the heating element. ‍

Step 2: Turn off the water‍

Turn off the water supply to your water heater. This is the cold water line that goes to the top of your water heater.

It is important to wait until the water in the water heater has cooled before flushing, as it can remain hot for a long time. You can start this step at night, after everyone in your household has run out of hot water.

Step 3: Open a faucet‍

Open a hot water tap somewhere in your house. If you want to drain your water heater faster, a tub faucet will likely have the highest flow rate in your home. ‍

Step 4: Connect a hose to the drain valve‍

For this step you will need a hose that you will connect to the drain valve on your water heater. Then run the hose to a drain, either inside your home or outside. A normal garden hose will do. Make sure the hose is securely attached to the water heater drain valve to reduce the possibility of splashing when the valve is opened.

Step 5: Open the drain valve‍

After your hose is connected and positioned outdoors or at a floor drain, open your water heater’s drain valve and allow the tank to drain completely. ‍It will probably take 30-40 minutes for a 40 gallon tank water heater.

Step 6: Turn the water supply back on and rinse

To remove the accumulated agitation from the bottom of the water heater tank, you must flush the water heater with fresh water from the cold water valve. When the tank is completely empty, turn on the cold water supply at the top of the tank. Then allow the water to flow through the water heater and out of the water heater drain valve and pipe for about 5-10 minutes.

Repeat this process at least 2-3 times to remove all debris. You’ll know your water heater has been successfully flushed when the water runs clear from the end of the hose. ‍

Step 7: Fill the tank‍

After your water heater has been flushed and all deposits removed, it is time to fill it. Close the drain valve and remove the hose. Then, with the cold water source still on, allow the tank to fill. You’ll know the tank is full when water comes out of the hot water faucet you left on, even though the water won’t be hot.

Step 8: Turn the water heater back on

Once it’s full you have to turn the heating back on to get it, well… hot!

With a gas water heater, you will need to refill the gas into the water heater. Then turn the steering wheel to Pilot and click the ignition switch 2-3 times. Check the light to make sure the pilot is working. On many models, a green light will start flashing to let you know it’s working.

You may need to reset the dial to the desired thermostat setting. Consider keeping the heat setting between 120 and 130 degrees, especially if you have children at home. It should keep your water hot enough for a shower, but not so hot that the water can burn you.

If you have an electric heater, you will need to turn that circuit breaker back on to power your electric water heater. Listen for a low hum from the machine and you’ll know it’s back up and running. You should have hot water in about 45 minutes. Because you didn’t touch anything with the thermostat when you turned the unit off, it will return to the temperature you set it to before you flushed the water heater.

That’s it! Now your water heater is successfully flushed and ready to run again at maximum efficiency. By following these simple steps, you can get the most out of your water heater year after year – just make sure you include it in your maintenance schedule for next year too.

If you have any questions about performing this maintenance, call us at (540) 501-6327. Our experienced technicians are available to answer your questions.