featuring a gold-flash contact coating to maintain signal integrity in low-current applications and a high-density footprint optimized for 4-inch snap track mounting

Is 28M97 compatible with all Lennox furnaces

listen for the reversing valve shifting

the FUS0823 is the direct replacement for S8402-091

Reznor 177633 Pressure Switch Els PW 17895 featuring a gold-flash contact coatingThe Reznor 177633 Pressure Switch is a critical OEM replacement part designed for precision monitoring within commercial gas heating systems. Engineered for unit heaters and duct furnaces, this combustion air pressure switch kit is factory calibrated to a 0. 50" W. C. setpoint (water column). The Reznor 177633 ensures safe ignition sequences and reliable venting verification by detecting proper differential pressure before allowing the gas valve to