The Lennox 49W66 Ignition Control Board is the heavy-duty OEM replacement for legacy 790-311 and 102186-01 modules. Designed for direct spark ignition (DSI) systems, this 24VAC control board is a critical integrated component for Lennox GCS16 rooftop units and commercial series. It features a 30-second pre-purge cycle and an 8-second ignition trial, providing precise timing to ensure safe combustion. As a veteran-grade HVAC replacement part, it manages the spark transformer via a Rajah terminal and includes a 3-trial ignition sequence with a 5-minute recycle delay to prevent nuisance lockouts. For technicians performing furnace board troubleshooting, this board effectively resolves ignition failure codes and inconsistent flame rectification issues. Its rugged black housing and wide operating temperature range (-40°F to 176°F) ensure durability in demanding rooftop environments, maintaining HVAC system compatibility and performance across diverse seasonal extremes. Key Benefits Direct OEM Replacement: Engineered to replace 790-311, 44L59, and 102186-01 without field modifications. Enhanced Safety Logic: Features a 30-second pre-purge and 3-trial ignition sequence to safely manage gas flow. Commercial Grade Durability: Rated for ambient temperatures up to 176°F, ideal for high-heat rooftop applications. Technical Precision: Integrated 24V direct spark ignition control ensures reliable pilotless operation and improved energy efficiency. Common Questions What does a red flashing light on the Lennox 49W66 indicate? Usually, a specific blink pattern points to ignition lockout or a low pressure switch fault; always verify the diagnostic code on the unit's access panel. Can I use this board for an intermittent pilot system? No, this is specifically a Direct Spark Ignition (DSI) control; ensure your system uses a spark-to-burner configuration. How do I fix a 'Trial for Ignition' failure? Check the flame sensor for carbon buildup and ensure the spark electrode air gap is within manufacturer specifications before replacing the board. This item is not eligible for free shipping. Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
