What does a fast-flashing LED on this board indicate

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and Coleman modulating furnaces

extending the service life of the heat exchanger by preventing flame impingement

High Flow Efficiency: Delivers a 14 Cv flow factor with optimized internal geometry to minimize pressure drop in gas trains

Lennox 18Y77 Blower Wheel 319825-402 What does a fast-flashing LEDThe Lennox 18Y77 Blower Wheel is a precision engineered 15x15 centrifugal component designed for high performance air delivery in commercial and residential Lennox HVAC furnace and air handler assemblies. As a direct replacement blower wheel, this unit is critical for maintaining the specific static pressure required for optimal heat transfer across the evaporator coil and heat exchanger. It features a 15 inch diameter and 15 inch width, engineered to