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Noritz releases new and improved, hard-water treatment product to increase efficiency and longevity of tankless water heaters.

The adage, “If it isn’t broken, don’t fix it,” has a loophole that puts Noritz and its customers well ahead of the game. As the leader in energy savings and superior hot-water delivery, Noritz recommends a new philosophy: “If it works, let’s make it even better.”

With the new Scale Shield, Noritz did just that.


What is Scale Shield? The new Noritz Scale Shield (SS-HB-3) offers an alternative method to treating hard water entering a tankless water heater for heating. Not only does it prevent the buildup of hard water minerals, but it will also lessen the maintenance workload for a homeowner and reduce the footprint inside the home by eliminating the need for a water softener.

To prevent limescale from forming in the water heater from calcium suspended in the incoming water, Scale Shield uses a polyphosphate material for sequestration of the calcium before it enters the heater. Installed in the water heater’s water-supply line, Scale Shield renders the calcium harmless, sending it down a household drain.

What is hard water? The groundwater in certain regions of the United States — especially in the southern sections of the country, but also the Middle West — contains an abundance of dissolved calcium and magnesium. When a water heater heats this “hard” water, the dissolved calcium and magnesium comes out of the liquid in the form of a chalky material. The chalk coats pipes, fixtures and fittings, creating an insulating layer that can undermine the efficiency of the water heater and the performance of the entire plumbing system.

If this buildup becomes excessive, the water heater may overheat, as it struggles to raise the temperature of the water through the limescale. The inevitable result: bigger fuel bills, reduced water heater longevity, and higher equipment and maintenance costs for the homeowner.

The traditional method of combating hard water is to treat it with a water softener. The problem is, these appliances take up a substantial amount of space in the home. Softeners also add to maintenance chores, because the salt supply inside must be routinely replenished. Also, this salt and its residue eventually find their way down a household drain, causing damage to the environment.

The original Noritz Scale Shield offered superior limescale prevention and corrosion control within the water heater and the overall plumbing system. It’s successor incorporates a number of important upgrades and innovations that provide even more effective treatment of hard water:


Built into the new Scale Shield is a sediment filter that removes particulate matter from the water. This 5-micron filter sifts through the debris, while introducing the polyphosphate additive to the water. This additive coats the calcium particulates, preventing them from releasing out of the water when heated; instead, they go harmlessly down the drain.


Two pressure gauges allow the homeowner to manually check pressure levels. As the particulate matter and debris collect within the filter, the buildup causes water-pressure loss in the house, indicating that a replacement filter is needed. To replace the filter, the homeowner simply unscrews the housing, removes the old cartridge, and replaces it with a new one.


The new Scale Shield also uses a different treatment medium than its predecessor. A powdery substance replaces the original’s bead-like material, increasing the efficiency of water treatment and reducing corrosion caused by chlorides, silica and dissolved iron. Although Noritz recommends a 12-month replacement timeframe at 15-grain hard water or less, the increase in media size offers a slightly extended lifespan for the product.


The new Scale Shield is compatible with all Noritz residential tankless water heaters and combination-boiler models. It contains a 0.75-inch stainless NPT inlet and outlet connections and, as previously noted, connects the cold water-supply line to the tankless water heater.


The manufacturer’s suggested retail price for the updated Scale Shield will be roughly the same as that of the original unit. Meanwhile, homeowners will reap cost-savings through lower maintenance costs and a reduced need to periodically descale their Noritz tankless water heaters — even in locales with seriously hard water.

In addition, by reducing limescale, the new Scale Shield inevitably boosts the longevity of the unit, while also minimizing scale buildup in other plumbing fixtures and fittings, thus lowering cleaning and other maintenance expenses.

“Installing Scale Shield is a significantly smaller cost burden than replacing your water heater’s stainless-steel heat exchanger due to excessive scale buildup,” explains Noritz lead engineer Randall Oshiro. “All of these cost and time savings, without a doubt, greatly enhance the value of the homeowner’s tankless water heater investment.”

Now available through Noritz plumbing wholesaler-distributors or on their parts and support website, the product will be sold in a kit (SS-HB-3) that includes a wall bracket, wrench, lubrikit, and pressure gauge.

The kit also includes one HBC-3 cartridge, and individual cartridge replacements will be sold through the website. The kit also has a 12-month warranty for parts only.