The Automated Oxygen Control System (AOCS) is a closed-loop system, measuring exhaust excess 02 (%) that makes precise, real-time adjustments to fuel gas or air input to continuously maintain optimum fuel:air ratios. The AOCS replaces imprecise components and compensates for changes in combustion air temperature and humidity, as well as gas composition, resulting in reduced maintenance costs, longer burner tube life, lower harmful emissions and material fuel savings. The AOCS is designed for new installations, rebuilds or enhancing existing combustion systems. With its rugged oxygen sensor connected directly to the AOCS’ on-board microprocessor, the stand-alone system detects and corrects both lean and rich burning combustion to a user-defined excess oxygen concentration setpoint. Fine adjustments to fuel gas or air are accomplished with IRISvalve™ technology.