How to Maintain a Tankless Water Heater for Long-Term Efficiency

Posted January 2, 2014

Tankless, or on-demand, water heaters are innovative appliances that provide an endless supply of hot water while saving energy by heating water only when needed. However, these high-tech devices are also among the most complex plumbing systems in your home, requiring regular maintenance to ensure proper operation and long-term reliability.

Why Routine Maintenance Is Important

Regular maintenance keeps your tankless water heater functioning efficiently and prevents potential issues like limescale buildup and clogged filters. Neglecting maintenance can lead to reduced efficiency, higher energy bills, and costly repairs.

1. Removing Limescale Build-Up

Over time, minerals such as calcium and magnesium can accumulate inside the heating chamber of your tankless water heater. This limescale buildup reduces efficiency and can damage the system. To prevent this, the unit should be flushed annually to remove these mineral deposits.

Steps to Flush Your Tankless Water Heater:

  1. Turn off the power and water supply to the water heater.
  2. Attach a hose to the flushing valves on the unit. Ensure the other end of the hose is placed into a bucket filled with white vinegar.
  3. Open the flushing valves and allow the vinegar to circulate through the system for approximately 45 minutes to one hour.
  4. Close the flushing valves, remove the hoses, and restart the water supply and power.

Always refer to the manufacturer’s instructions for specific steps and safety precautions for your model. If you’re unsure, consult a professional plumber to handle this task.

2. Cleaning the Screen Filter

Another essential maintenance task is cleaning the in-line screen filter, which prevents debris from entering the water heater and affecting its performance. This task should be performed periodically, especially in areas with hard water or sediment-prone water supplies.

Steps to Clean the Screen Filter:

  1. Turn off the incoming water supply to the unit.
  2. Locate the screen filter on the inlet fixture of the water heater’s cabinet.
  3. Unscrew the plug to remove the filter.
  4. Rinse the filter under running water to remove accumulated debris.
  5. Reinstall the filter securely and turn the water supply back on.

Keeping the screen filter clean ensures optimal water flow and prevents blockages that can strain the system.

Additional Maintenance Tips

To keep your tankless water heater running smoothly, consider these additional maintenance tips:

  • Install a water softener if your home has hard water to reduce mineral buildup.
  • Inspect the venting system to ensure there are no obstructions or leaks.
  • Schedule an annual professional inspection to check for wear and tear or potential issues.
  • Monitor the water heater for error codes displayed on the control panel and address them promptly.

Need Help Maintaining Your Tankless Water Heater?

At ABC Plumbing, Sewer, Heating, Cooling, and Electric, we specialize in tankless water heater maintenance, repairs, and installations. If you need assistance with flushing the unit, cleaning the screen filter, or addressing other maintenance needs, our experienced technicians are here to help.

Scroll further down this page, locate the location closest to you, and click the phone number to call us. Let us help you keep your tankless water heater efficient and reliable for years to come.

ABC Plumbing Locations

Arlington Heights, IL

220 W Campus Dr
Arlington Heights, IL 60004
Phone: (888) 991-3942

Evanston, IL

828 Davis St UNIT 205
Evanston, IL 60201
Phone: (888) 868-9369

Downers Grove, IL

1001 Ogden Ave LL4
Downers Grove, IL 60515
Phone: (888) 412-3566

Tampa, FL

4326 W El Prado Blvd Suite 7
Tampa, FL 33629
Phone: (888) 594-9030

Largo, FL

11701 S Belcher Rd Suite 127
Largo, FL 33773
Phone: (888) 465-9799


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