Berko 4520-2048-000 Limit Switch Includes two dial stop pins

Includes two dial stop pins that can be field-trimmed for custom fitting and precise alignment

you know that a compromised York furnace limit switch isn't just a nuisance—it’s a safety violation

and 51 boiler controls

Can I use this to replace part S1-029-20423-043

Can this be used for R-410A systems

Berko 4520-2048-000 Limit Switch Includes two dial stop pinsThe Berko 4520 2048 000 is an OEM 135F CO Auto Limit Switch designed for high performance thermal regulation in Marley Engineered Products and QMark 900 Series B heating systems. This 2 pole limit switch operates with an automatic reset mechanism, functioning as a critical safety component that opens on temperature rise to prevent overheating. Engineered for HVACR technical specifications, it features a single pole single throw (SPST) switch action,