This varies by the boiler's BTU rating

Key Benefits Universal Compatibility: Optimized for standard 3/8" damper shafts and splined actuator shafts common in Barber Colman and Schneider Electric systems

or visible soot around the pilot door

Its NEMA 4/4X ingress protection rating

using this HVAC high limit switch maintains the original engineering specifications for safety and performance

York S1-025-37494-000 Limit Els PW 17895 This varies by the boiler'sEnsure critical thermal safety in your HVAC equipment with the York S1 025 37494 000 Auto Limit Switch. This high performance safety device is specifically engineered for precise system protection, featuring a fixed 170F opening temperature and a 140F closing temperature for automatic reset functionality. As a vital component for high limit oversight, this York HVAC furnace limit switch prevents heat exchanger damage by breaking the circuit if