For T-4000 series units equipped with specialized security screws

this specific model requires a 120V control signal to the coil

What are the benefits of a hubless aluminum fan blade

but the A61 is the standard for quiet HVAC operation

The Conbraco 10-418-15 carries the 'HV' symbol and is National Board capacity certified

Lennox 12F19 Flame Sensor For T-4000 series units equippedThe Lennox 12F19 Flame Sensor is a critical safety component designed for precise flame rectify detection in residential and commercial gas fired heating systems. This genuine OEM part is engineered to monitor the burner's pilot or main flame, sending a continuous microamp signal to the furnace control board. If the 12F1901 furnace sensor fails to detect a flame, it immediately signals the gas valve to shut down, preventing hazardous gas accumulation.