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  • How to Flush a Water Heater


  • March 1, 2021

    Did you know one of the most common causes of failure for your water heater is something you can fix at home?

    It’s true. One of the most common causes of water heater failure is mineral sediments building up and leading to several other problems. All water has some sort of mineral composition inside of it. Those minerals accumulate on the inside of your pipes, faucets, and especially your water heater. Flushing your water heater can remove some of these mineral deposits from your system.

    Are you ready to flush your water heater? We’re excited to help. Check out our comprehensive guide for flushing your water heater below and if you need any help, give us a call today.

    Preparing To Flush A Water Heater

    Water heaters come in two main varieties: electric water heaters and gas water heaters. Both types of water heaters will need some preparation. Gather a large empty bucket or bowl, a hose, and a portable pump if your water heater is in the basement.

    Preparing to Flush An Electric Water Heater

    Preparing to flush an electric water heater is easy. You simply turn off the power to your water heater. Usually, this is done by going to your breaker box and shutting off the breaker associated with your water heater. This will shut off the power that goes to your water heater.

    Preparing To Flush A Gas Water Heater

    Does your water heater use gas to operate? Then you likely have a gas water heater. Here’s how to flush your gas water heater:

    Turn Your Water Heater’s Thermostat to “Off”

    Your water heater will likely have a knob that controls the thermostat at the bottom of the water heater’s tank. Later, you will need to relight your pilot light.

    Turn Off The Gas

    Look for the gas pipe that leads to your gas water heater’s thermostat. Find the valve on the pipe and turn it to the off position.

    Flushing the Water Heater

    Once you’ve turned off everything leading to your water heater, the steps for gas and electric water heaters are fairly similar.

    Turn Off The Cold Water

    There will usually be a cold water supply sending water to your water heater. The valve will often be located near the top of the water heater. Find the valve for that supply and turn it off. 

    Turn On The Water In A Sink

    Go to your bathroom and kitchen sinks and turn on the hot water. You’ll need to let these sinks run at full blast the entire time you’re flushing the water heater to make sure the pressure doesn’t form a vacuum and damage your pipes. No water will come out but set these sinks to full blast anyway. 

    Relieve Pressure & Cool The Tank

    Look around your water heater for the pressure relief valve. Next, grab a large bowl or bucket and place it underneath the pressure relief valve’s drainage pipe. Release the pressure on the relief valve and stand out of the way of the hot water that will drain out.

    Wait for the water to stop draining and for the water in the tank to cool down. This can take an hour to two hours.

    Drain The Tank

    First, locate the drainage valve or spigot. Once you’ve found it, run a hose from outside and connect it to the valve. Make sure that your hose flows outdoors or into a bucket.

    Sometimes your water heater will be deep in your basement and running a hose from outside isn’t feasible. If this is the case, you may want to get professional assistance or use a portable pump to pump the water to the ground floor and then into a hose outdoors. 

    Once you have your hose and valve connected, turn on the valve and allow the tank to fully drain. Look at the water to make sure it no longer has mineral deposits or sediments flowing out.

    Clean Up Your Space

    Now that your tank is flushed and the water is clear, put everything back to the way it was. Close the drainage valve and take off the hose. Shut the pressure relief valve and go turn off the sink you had running during the whole process.

    Next, go turn back on the cold water supply. This will allow you to refill your tank and have hot water again. Once it seems full, open the pressure relief valve in case any air is trapped.

    Turn on the gas and relight your pilot light if needed. 

    Flush Your Water Heater with the help of J.A. Bertsch

    A gas or electric water heater needs to be properly maintained due to the calcium, lime, and hard water deposits that can accumulate over time. Our team at J.A. Bertsch is here to help. We offer professional residential water heater repair services, including flushing your water heater. Our technicians serve all of Kootenai County. Book your appointment at 208-635-5480.