How to Flush A Tankless Water Heater


Flushing out sediments in your tankless water heater is one way to keep your appliance working as it should. If you aren’t a professional or you’ve never done it before, the idea of doing it on your own can be intimidating. The good news, however, is that the process is actually easy. Below, we’ll show you how to flush a tankless water heater.

The first thing you need to do is to gather your tools and materials. For this, you’ll need:

  • 4 gallons of white vinegar
  • 5-gallon bucket
  • 2 stainless steel washing machine hoses
  • A submersible pump

Next, find the shutoff valves. In most models, they are the color-coded handles you’ll find underneath your heater. Make sure that the handles are perpendicular to the pipes as that means the unit’s off.

After that, unplug your heater from the wall socket and unscrew the cold water service valve. However, before you actually do that step, make sure that you have your bucket ready to catch the water that’ll come out.

Once you are done with the cold water side, you can do the same with the hot water side. Be careful not to burn yourself. Ideally, when you flush your hot water, you should do it when no one has washed the dishes or taken a hot shower.

Get your white vinegar pump ready. Do this by emptying the gallon you’ve previously filled with water and fill it with white vinegar. Attach the hose from the cold water service valve into the top part of the sump pump.

Place the pump into the vinegar before you plug the unit into the wall. As soon as you plug it in, it should start to circulate the vinegar to the service valves.

Leave the unit for about 60 to 90 minutes.