When diagnosing a failed condenser fan or small blower

Broad Series Compatibility: Direct-fit replacement for Maxitrol RV81

When performing annual maintenance or a heat exchanger inspection

the switch is faulty and requires replacement

making it fully compatible with newer R407C refrigerants while maintaining support for R22 service applications

Lennox 59W74 Pressure Switch 319852-301 When diagnosing a failed condenserThe Lennox 59W74 Pressure Switch is a critical safety component engineered for precision monitoring of inducer motor performance and flue draft integrity. This OEM Lennox furnace pressure switch transitions at a fixed set point of . 80"wc, ensuring the combustion process only initiates when proper negative pressure is established. Featuring a Single Pole Single Throw (SPST) configuration and dual 1 4" barb connections, this switch provides a reliable