Model CBEX Elite attains operating efficiency and emits fewer air pollutants, says its manufacturer. The packaged boiler incorporates ultra-low NOX burner technology that results in meeting sub-5 ppm NOX on select models without selective catalytic reduction (SCR). The product’s low-NOX burners produce 30 ppm NOX and maintain 3 percent O2 across the full operating range with 10:1 turndown. The system automatically adjusts to changing environmental conditions. Available options include a variable-speed drive control and NOX trim for controlling the ultra-low NOX burners.