However, if you don't maintain your tankless water heater properly, it will operate less efficiently, reducing the savings you can experience versus the operating cost of a traditional tank unit. So, spend a little time on the maintenance tasks described below — or hire a recommended plumber who can do it for you — and you'll be well on your way to taking full advantage of the benefits a tankless water heater can provide.
Check and clean the in-line screen filter
Periodically inspect and clean the filter located on the water inlet side of your tankless water heater. It's best to hire a licensed plumber for this job. If you're a do-it-yourselfer, please do your research before attempting this task. Note: Never use chemicals to clean your water heater, as it will enter your drinking water. Use vinegar instead.
Flush the System
To protect your tankless water heater from a harmful buildup of lime and scale, flush it periodically. You can find a plumber on Kudzu to help you. As noted above, be sure to flush it with vinegar and not chemicals that can contaminate your water supply.