The PHVAC industry is ever changing and ever evolving.

Suppose I was to tell you there exists a tankless water heater you could install on the hardest of hard water that would never, ever have to be descaled and that its heat exchanger’s water pathways would look almost as clean as the day it was born. You’d think I’d gone off my meds — right? 

At every AHR trade show, I look for the one product that is a true game-changer. One that stops me dead in my tracks, grabs my attention and doesn’t let go. There were literally hundreds of contenders, as there are at every AHR show, but the new A. O. Smith X3 tankless technology is, without question, a stunning achievement that once and for all eliminates the No. 1 enemy of tankless water heaters — scale buildup. 

A Routine Conversation

How many times have you almost landed another tankless water heater sale only to have that fall apart when you told the owners you will need to come back once each year to descale the heat exchanger or the warranty will be voided? 

“How much does that cost?” they wonder. 

In an effort to overcome that objection, I even offered the first annual descaling for free (built into the upfront cost, of course). You could see the wheels turning in their heads as they contemplated several decades of annual descaling service charges. 

“Thanks, but we’ll stick with our tank-style water heater.” 

Outside the boundaries of our municipal water company territory, we have significant zones of hard water with 14-grains and harder water. A tankless installed there will need to be descaled at a minimum of once each year, and we all know just how receptive the average homeowner is to the call. 

“Hello — it’s time for your annual tankless cleaning.” 


Kind of like air handler air filters. 

“I change mine on a regular basis,” they say with a straight face while you have just removed what looks like a Wooly Mammoth! Let’s face reality: No one likes routine maintenance, and we don’t break into service equipment. 

Innovation Never Ends

David Chisolm, vice president of marketing at A. O. Smith, opened the morning press conference at AHR Expo by talking about innovation and revealed an interesting tidbit: Back in the 1870s, grain silos featuring a white top with AOS stamped on it were actually glass-lined tanks produced by A. O. Smith! 

Then he spoke about Henry Ford and the well-known automation in mass-producing the Model-T. Turns out C. J. Smith, A. O. Smith’s father, was the one who partnered with Henry Ford to develop the automation! 

“The common theme you hear in all of that is innovation,” Chisholm said. “How do we find problems, dig into those problems and then put our innovative minds to work?”

Jeff Ogan, director of project management and technical support, was introduced by Chisolm as “the Steve Jobs” of the water heater industry. Ogan began his career seven years ago with A. O. Smith as the tankless product manager. The X3 has been 4 1/2 years in the making and “is really the result of talking to thousands of contractors who have come through our plants on an annual basis. [Telling us] what the headaches and pain points are in their lives,” Ogan explained. 

Eighty-five percent of the U.S. has hard water, which is the Achilles’ heel of tankless water heaters. A. O. Smith set up accelerated testing in a facility in Roswell, New Mexico, where the hardness ranges from 40 to 75 grains of hardness! And all tankless water heater manufacturers have exclusions in their warranty that’s a get-out-of-jail-free card if failure is due to buildup of scale. 

You and I know who gets the blame — the contractor — if warranty is denied. We’re right there on the front line. 

Imagine this problem going away, and that you no longer need to twist arms regarding an annual descaling visit? Face facts: Descaling never takes a heat exchanger back to its original condition, so efficiency losses become built-in, and this doubles the cost of ownership for our customers. 

How is it possible that adding a canister of some secret technology can eliminate the need to descale a tankless water heater ever again? I had an opportunity to talk privately with Chisolm to pose that question. 

The Journey and the Result

A. O. Smith identified scale buildup as the No. 1 contractor pain point, so they set out on a course to find a resolution. (Remember the innovation quest?) They did something to speed up the innovation process — they bought a water treatment company and then locked up the innovators in both companies in a room with orders not to come out until they resolved this issue! Just kidding: They put the innovators from both companies together to hammer out a solution.

The first iteration was a canister filtration device that needed to be changed every few months — depending on how hard the water was. But, as Chisolm put it, “we all knew how frequently things like furnace filters get changed out and knew changing water hardness filters would also be neglected and then we’re back to scale buildup, so back to the drawing board. 

“Then came 6-month, then 1-year and then 3-year cartridges. It finally dawned on us that we were onto something truly different and the team began focusing on finding a solution that would last the lifetime of the tankless water heater — and we did just that!”

Freedom to offer tankless water heaters to anyone no matter the water hardness and never again need to schedule a descaling visit? The biggest PITA for both you and your customers is gone! Outstanding!

Naturally, I wanted to know the same question that you’re thinking: Is the water treatment cartridge available as a separate component so we can retrofit that into our existing tankless water heater installations? Unfortunately, it is not, but Chisolm did infer there is a possibility they will expand the technology to offer whole-house treatment for hard water. At present, we’ll have to settle for just the hot potable water side, but imagine the potential of offering whole-house treatment that doesn’t require salt for ion bed regeneration. 

I also wanted to know if the cartridge poses a significant reduction in water pressure and that answer was also no, which is a good thing for our customers. 

Like you, I am left to contemplate what mysterious goodness lies within that cartridge that can combat scale for the life of the tankless water heater and never once require being replaced. The only other hardness combatant claims I’d seen and read about deal with wrapping wire around the incoming water line to induce a flux-field that the manufacturers claim realigns the hardness molecules in such a fashion that they can no longer precipitate out of solution. I had to ask, and the answer was no, that is not how the A. O. Smith cartridge works. 

So there you have it: My choice for the AHR game changer. Boom! Mic drop. No doubt we’ll see all tankless manufacturers offering similar technology at the next AHR or the one beyond, but that’s what keeps this PHVAC industry alive, invigorating and innovative. Ever changing, ever evolving, and contractors and their customers are the ultimate beneficiary. AHR is the place to be if you want to remain ahead of your competition.   

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