How To Flush Your Tankless Water Heater

A tankless water heater has so many benefits, from its compact size to its ability to last for years with very little maintenance. That being said, tankless heaters do need occasional flushes to keep them working their best. We put together this quick guide explaining how often your tankless unit needs to be flushed and how you can do it.

How Often Should You Flush Your Water Heater?

Before we explain how, most people want to know how often a tankless heater should be flushed. The rule of thumb is that all tankless water heaters need a flush at least once a year; depending on your water quality, every six months or even every three months may be advisable. If you’re not sure about your water quality, your local propane company will likely have a recommendation based on your area.

Why Do You Need To Flush A Tankless Heater?

No matter what kind of water heater you choose, you need to flush it periodically to keep it performing well. All water has some kind of minerals that can build up inside water heaters, causing them to heat inefficiently (which wastes money) or even causing damage. Flushing clears these minerals out and ensures that your machine will be working at its top performance at all times.

How To Flush Your Water Heater

Finally, here are the basic steps to flushing your tankless water heater. Note that these should be assumed incomplete—always follow the instructions provided with your water heater for safe and accurate directions.

  1. First, turn off the power source and shut off the gas valve.
  2. Then close the attached water valves (our Rinnai tankless water heaters have three).
  3. Slowly remove the purge port valve caps—this must be done slowly in case there is pressure behind the cap.
  4. Attach hosing to each valve, then open the purge port valves.
  5. Pour in about 4 gallons of undiluted white vinegar (never use any other chemicals), then follow the purging instructions provided with your water heater.
  6. When finished, close the purge port valves and replace the caps, then restart your water heater following the instructions provided with your heater.
  7. Turn on the hot water at one of your sinks and let it run until all air has escaped. This may take several minutes.
rinnai tankless water heater

Euliss Makes Flushing Your Tankless Water Heater Easy

Although flushing your water heater yourself is doable, it has a lot of steps that have to be done correctly to prevent damaging the unit or causing safety issues. If you’d rather avoid the hassle, we can help! As your local propane company, we will service your machine, flush it, and make sure that your tankless water heater is functioning properly. Contact us today to learn more.

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