The importance of knowing the difference between Low NOx and UltraLow NOx when purchasing a new water heater.

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Nitrogen oxides are abbreviated as NOx; they are a family of toxic and reactive greenhouse gases. During combustion of fuel at high heat that is in the engine of a vehicle, boiler, water heater or furnace there is release of nitrogen oxide.  NOx is a brownish harmful gas which is released to the environment; therefore, the EPA placed forth regulations in order to limit the exposure to the most predominant form of NOx; that is nitrogen dioxide or NO2.

According to the EPA NOx is a chief contributor to:

  • Respiratory problems
  • Low water quality
  • Ground-level ozone
  • Acid rain and smog
  • Global warming
  • Toxic chemicals

Low NOx and UltraLow NOx

With the above-mentioned problems, it is very important to use proper venting in installing heating equipment. When purchasing your water heater there are two categories that you can choose from that is; the UltraLow NOx and the Low NOx. For an individual to choose between either the UltraLow NOx or the Low NOx you consider:

  • The output of energy which is expressed in joules per unit of NO2 emitted (expressed in Nona grams)
  • The capacity plus size of the equipment

Difference between Low NOx and UltraLow NOx

When it comes to the difference between the Low NOx and the UltraLow NOx, it is determined by the standards of the local EPA basing on the type of the heating equipment. When it comes to Low NOx, it can reduce the emission of NOx to 30 pm. Low NOx equipment uses FGR and is able to maintain 3 to 5% excess oxygen with strong controls. The turndowns are less than the ratio of 8:1.

For UltraLow NOx, the emissions are between 7 to 15 ppm. The burners use FGR, adjusted fuel/air ratios plus a staging in order to have low emissions. The UltraLow NOx can have 5 to 9% emissions of oxygen, a turndown ratio of 4:1 or 3:1. The UltraLow NOx technology is improving to conservative designs with an objective of being more efficient.

When purchasing a new water heater, it is very important for you to understand what kind of a heater are you purchasing? That is, is it Low NOx or UltraLow NOx? As they are ways you can use in order to reduce NOX release to the environment.