With a maximum inlet pressure of 1/2 PSI and a factory-calibrated outlet pressure range of 2

maintaining consistent CFM and improving indoor air quality

this is the official replacement limit switch for several generations of the Defender series

leading to sticking or electrical failure at the contacts

Trane CNT4991 Pressure Switch R-410A With a maximum inlet pressureThe Trane CNT4991 is a 10 inch SPST pressure switch engineered for precise atmospheric monitoring in high efficiency Trane and American Standard HVAC systems. This OEM air pressure switch features a single pole single throw (SPST) contact configuration, rated at 0. 1" WC (water column) for low pressure detection. It is designed to interrupt or complete the 24V control circuit (rated at 28 VA) when specific airflow or flue gas pressure thresholds are