Low-NOx Burner

A low-NOx burner is a combustion burner designed to cut the nitrogen oxide emissions a flame produces, and one influential version, developed from around 1986 by Australian inventor John Joyce after he researched how nitrogen oxides contribute to smog and acid rain, brought unflued gas heater NOx emissions down to roughly 2 nanograms per joule, about 4 parts per million at zero percent oxygen, compared with the 15 nanograms per joule that had previously counted as low and the 30 to 50 nanograms per joule a conventional blue flame burner produces. Late 1980s Australian health rules capped indoor nitrogen dioxide at 0.3 parts per million in classrooms, prompting the Australian Gas Association to cut its own allowable unflued heater emission limit from 15 to 5 nanograms per joule, a standard Joyce burner beat comfortably. Joyce won an Australian Design Award in 1993 for the SLE heater range built around his low-NOx burner and patented the technology in Australia, the United States, the United Kingdom, Japan, Italy and France; because an unflued heater loses no heat up a flue, a low-NOx unflued heater converts all the heat its flame releases directly into usable warmth, a full 100 percent combustion efficiency.