Tankless with X3® Scale Prevention Technology
X3® Scale Prevention Technology prevents scale build-up to reduce regular maintenance and extend the life of your water heater by up to 300%
X3® Scale Prevention Technology
Scale is the #1 enemy for tankless technology. With normal use, scale build-up occurs because minerals like calcium and lime naturally exist in hard water. This buildup decreases efficiency and increases the cost to operate the water heater. Regular descaling is required to prevent these issues.
A. O. Smith's X3® Scale Prevention Technology combines tankless technology with a built-in descaling process to achieve unparalleled protection on our many of our condensing gas tankless models.
Benefits of Gas Tankless Water Heaters with X3® Technology
Extends Life Up To 3 Times Longer
The new X3® Scale Prevention Technology eliminates particle build-up in the heat exchangers, preventing scaling and extending the life of the unit.
Maintains Like-New Performance
Tests showed tankless models with X3® Scale Prevention Technology maintained like-new efficiency after 15 simulated years vs. models without X3® technology, which showed a 10% efficiency reduction in just 1.5 years.
Never Descale Again. Ever.
X3® Scale Prevention Technology eliminates the need for regular scale-related maintenance as it prevents scale from accumulating.
"Peace of Mind" Scale-Inclusive Warranty Coverage
A. O. Smith stands behind this revolutionary product with the industry’s first ever “Peace of Mind" 15-year limited warranty, which covers scale-related failures should they occur.
Enjoy Instant Hot Water
Tankless water heaters with X3® Technology are approved to work with an external recirculation pump and cross-over valve (sold separately through APCOM).
Rebates & Tax Credits
Up to $850 in Local Utility Rebates may be available in your area!
*Gas water heaters with UEF of 0.82 or higher OR with a thermal efficiency of at least 90%. Local utility rebates available in limited geographical areas. For information on the Federal Tax Credit, go to: energystar.gov. Check with your tax advisor for applicability. Offer details and expiration may vary. See Rebate Center for details.
How it Works
Recirculation pump not included with all models
How X3® Scale Prevention Technology Eliminates Scaling Problems
Condensing gas tankless water heaters with X3® Scale Prevention Technology connect directly to the water line. When you open a hot water tap, the burner in your gas tankless water heater activates. As water flows through the unit, it quickly reaches the preset temperature by rapidly absorbing heat from the heat exchanger.
Our patent pending X3® Scale Prevention Technology allows mineral particles to pass through harmlessly while continually protecting the heat exchanger from scale buildup. This eliminates the need for regular descaling and extends the unit’s life up to three times vs. a tankless model without X3® Scale Prevention Technology.
Due to this direct heat exchange, these condensing gas tankless water heaters provide long-lasting, on-demand hot water. When the water tap is turned off, the unit shuts down to conserve energy.
Still Have Questions?
The Gas Tankless with X3® Scale Prevention Technology has been tested in various locations around North America, including Roswell, New Mexico, an area with some of the hardest water in the country, to ensure its performance can hold up in the harshest water conditions.
Yes, our tankless models with X3® Scale Prevention Technology are capable of being used with a recirculation pump when a cross-over valve is used. Cross-over valve sold separately.
Residential single-family applications with hard water concerns. Hard water is everywhere. In fact, more than 85% of American homes have hard water which adversely affects plumbing systems, including water piping, water fixtures, and the water heating system.
No, currently the 540X3, 340X3 and 240X3 models are designed for use in residential single-family applications where Easy-Link™ is not required.
Based on our research, stainless steel and copper heat exchangers fail at the same rate due to scale build up. That’s why it’s important to install an A. O. Smith tankless model with X3® Scale Prevention Technology.
Because this is our standard condensing gas tankless model that you’re already used to, they are compatible only with 3" or 4" venting. As long as the gas line is sized appropriately for the BTUs, ½" gas lines can be used based on national fuel gas codes or applicable local gas codes or as outlined in the instruction manual.
Product Comparison
Many factors affect the actual performance of a water heater. This represents our closest approximation of your likely experience with this water heater in your local area, but actual performance may vary depending on factors beyond our ability to control or estimate.
Find A Local Water Heater Pro
A. O. Smith water heaters are professionally installed by local independent contractors.
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Why A. O. Smith?
A. O. Smith is a leading manufacturer of both residential and commercial water heating technologies, including the #1 most specified commercial water heater.
For more than 145 years, we’ve developed state-of-the art products that push new boundaries and improve the lives of our customers.
We combine cutting-edge technology with committed people who take pride in providing the very best support for our customers.
Our products are put through rigorous quality and endurance testing so now matter where hot water is needed, A. O. Smith can provide a solution you can count on.