Maintaining a Tankless Water Heater
Over time, minerals will accumulate on the inside of the tank's heating chamber. To remove this mineral build up the unit should be flushed regularly, at least once a year, to remove the accumulated limescale deposits. The steps involved in flushing the tank will vary by manufacturer, but the procedure typically involves attaching a hose and flushing the tank with vinegar. See your owner's manual for details.
Cleaning the Water Heater Screen Filter
Another important tankless water heater maintenance task involves cleaning the in-line screen filter to remove any accumulated debris. Turn off the incoming water supply. The filter is located on the inlet fixture on the cabinet. Unscrew the plug to remove the filter. Rinse the filter off and reinstall it on the unit. Consult your owner's manual for the location of the screen and important safety information.