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Don't Let Water Heater Maintenance Scare You!
Updated over a week ago

The Importance Of Flushing And Cleaning Your Tankless Water Heater And Why You Shouldn't Be Afraid!


Regardless of where you purchase your tankless water heater, the manufacturer will always recommend regular maintenance, such as flushing and descaling. It's required if you expect to keep your appliance running optimally for years to come.

Your water heater should be flushed and descaled approximately every 6 months to avoid any lime and mineral deposit build-up inside of the exchanger. Sediment build-up is especially dangerous for the health of your water heater as it might clog the heating element and prevent it from performing as it should.

This may seem like a daunting task at first, but we've created a system that takes the fear out of the entire process. Check out the video below to see how we are taking the fear out of what should be an easy task!

Why flushing is important

The heat exchanger in your tankless water heater is made up of small, narrow passages that the water flows through when it is being heated. Over time, if those passages are not flushed and cleaned out, debris, limescale and sediment can build up and clog those passages making your water heater overheat and can even make it completely stop operating.

If you fail to follow the guidelines of flushing and descaling every 6 months and your water heater becomes damaged due to neglect of required maintenance, the warranty will be void. Any damage related to lime scale buildup is not covered by the warranty.

How To Flush Your Tankless Water Heater

Flushing and descaling your tankless water heater is really a simple task and we have created a kit to keep it that way. The following instructions are going to be based on a scenario in which you’re using our EZ Flush Kit and you have service valves installed.

  1. Turn off the power and gas to your tankless water heater.

  2. Close the shutoff valves on your hot and cold water lines so that no water from your home or water source can enter the water heater.

  3. Use the service valves to connect the EZ Flush Kit to the cold water line. Your kit’s connections are marked inlet/outlet.

    • Using one of the supplied hoses, connect the hose to the cold water inlet on your service valve and then connect the other end of the hose to the port near the bottom of the kit marked “outlet”.

    • Using the other supplied hose, connect the hose to the hot water inlet on your service valve and then connect the other end of the hose to the port near the top of the kit marked “inlet”.

  4. Connect your power cord to the port on the kit and plug it in.

  5. When you purchased your kit, you were provided with 1 Qt. of descaler solution. Pour that into the top basin of the kit and dilute with 1 gallon of water.

  6. After you’ve filled the basin with your water and solution, do one last check of the following:

    • Make sure the gas is off.

    • Make sure the service valves are turned to the position that cuts the water from the house off. NO WATER from your water source should be able to enter the water heater. NOTE: This can be dangerous and activate the water heater during flushing. This should not happen. Your water heater should be powered off and disconnected from all gas and water connections except the Flush Kit.

  7. You may turn the kit on using the Red power switch on the kit.

  8. Allow the kit to flush the water heater for approximately 30-45 minutes.

  9. When you are finished, follow the instructions that came with the kit for correct cleansing and storing of the kit.


Flushing your water heater isn't all that is a part of keeping your water heater healthy and running great. You'll want to make sure you're checking the following as well:

  • Take out the water filter on the water inlet line and rinse out to be sure no debris is stuck in the filter.

  • If you have an outdoor model, take the cover off once a year to make sure that no bugs have made homes inside. They shouldn't, but they like the warmth inside of the heater and it's not uncommon for them to hang out in there.

  • If your water heater is an indoor model, please make sure you have a condensation drain installed so that no condensation flows back into the water heater's exchanger. If a condensation drain is not installed and damage is caused to the exchanger, it will void your warranty. It's important to take the cover off once a year to make sure your condensation drain is working and no damage is occurring inside.

If you ever have questions about maintenance on your water heater, please reach out to our team. We are always happy to help!

Team Eccotemp

Protect your Tankless water heater using our Eccotemp EZ Flush System Descaler Kit!


For additional information, please feel free to email our support team at [email protected] or call us at 866-356-1992.

Thank you for choosing Eccotemp Systems for your hot water needs!

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