Lochinvar & A.O. Smith 100109935 Flue Switch 326070-701 Technicians rely on the 42-21593-01

Technicians rely on the 42-21593-01 to protect electrical circuits from voltage spikes and inrush current during startup sequences

If the unit displays "air temperature out of range" codes or continues to run regardless of the setpoint

critical for maintaining proper refrigerant subcooling

How do I know if my Goodman collector box needs replacement

This cover is proprietary to the Johnson Controls T-4000 series

Lochinvar & A.O. Smith 100109935 Flue Switch 326070-701 Technicians rely on the 42-21593-01Maintain the exhaust integrity and operational safety of your high efficiency heating systems with the Lochinvar & A. O. Smith 100109935 Flue Switch. As a critical safety component, this blocked flue pressure switch is engineered to detect vent obstructions and immediately signal the control board to terminate the ignition cycle, preventing hazardous flue gas recirculation. This genuine OEM part is the designated 100109935 replacement for 9004550215,