Meet the New Noritz Low-NOx Tankless Water Heater
Noritz is committed to reducing pollution by coming in under emissions standards in California and — eventually — other states
Nitrogen oxides (NOx) are air-polluting compounds that react with the atmosphere to produce ozone and acid rain. Ozone creates smog and reduces the quality of breathable air, while acid rain can damage crops and unbalance entire ecosystems.
Human activities trigger the formation of most NOx emissions, since the compound is created when fossil fuel is burned at high temperatures, such as during the gas-combustion process in an automobile. Cars are some of the largest producers of NOx, which is why owners across the country must submit their vehicles to periodic emissions testing.
NOx Emissions Regulations
NOx emissions are not limited to the auto industry, however. With the high temperatures generated by their combustion process, water heaters are also sources of NOx 
emissions and can contribute to air pollution. To limit these emissions, several air quality management districts in the state of California require that water heaters release no more than 20 parts per million (ppm) of NOx emissions.
“California tends to be a trendsetter for green energy requirements,” says Noritz engineer Eric Manzano. “Other states look to the Golden State as an innovator in this regard, and I wouldn’t be surprised if more begin to adopt these low-NOx emissions standards.” In fact, Utah recently became the first to adopt the same low NOx requirement, effective July 2018.
Why the Noritz Low-NOx Units Are Ahead of the Game
Noritz has been able to not only meet California’s strict, low-NOx standard, but actually exceed it, with its latest additions to the EZ Series line of ultra high-efficient condensing tankless water heaters. The Energy Star-rated EZ98-DV and EZ111-DV heaters have a nitrogen oxide-emissions level of only 14 ppm, or six ppm less than the California requirement.
Manzano explains that the low-emission levels in the EZ models derive from a significant redesign of the traditional tankless model. “We made alterations to the burner and gas valve to far exceed the requirement.” Pre-mixing makes the fuel/air mixture more even. Since NOx is more prone to form in pockets of extra air or lower levels of gas, regulating the fuel/air mixture helps keep this process better under control.
The Noritz Low-NOx Tankless Water Heaters Are Future-Proof
With their low-NOx emissions, the EZ units are prepared to meet not only the current code, but also future revisions that might lower the maximum emissions level even further. The company will also be ready if and when other states join California and Utah in implementing similar requirements.
The EZ Series, with its top-mount water connections and multiple venting options, is best known among contractors for its ease of installation when replacing storage-tank water heaters. But the low-NOx rating is a major benefit for the environment as well, says Manzano: “With these new water heaters, you can enjoy hot water on-demand, with minimal energy use and in an environmentally friendly way.”
For more information on the EZ Series, please visit https://www.ezseries.noritz.com/