York S1-02538737000 Limit Switch 160F Open 140F Close

Product Description

The YORK S1-02538737000 is a high-limit switch designed to protect gas furnaces and air handlers from overtemperature conditions. It opens the control circuit at 160 degrees F and automatically resets by closing at 140 degrees F, providing a 20-degree F differential. This auto-reset design eliminates manual intervention after a brief overheat event and restores normal operation once the system returns to safe temperatures. Licensed HVAC technicians install this switch as part of furnace safety control systems, where it acts as a primary or secondary high-limit device to prevent heat exchanger damage and nuisance shutdowns.

This limit switch is suited for residential and light commercial gas furnace applications. It mounts in the supply air plenum or heat exchanger compartment, where it monitors air or component temperatures during heating operation. The auto-reset function makes it appropriate for systems where repeated manual resets would be impractical. Installers replacing a failed high-limit switch should verify the setpoint values match the original equipment specification before installing this part.

Key Features

• Opens at 160 degrees F to interrupt the control circuit on overtemperature
• Closes at 140 degrees F for automatic reset without manual intervention
• 20-degree F differential provides stable switching and reduces short-cycling
• Auto-reset design suits furnace applications where continuous monitoring is required
• OEM YORK part ensures fit and function consistent with original equipment specifications

Compatibility

Designed as an OEM-style replacement high-limit switch for YORK gas furnace and air handler systems requiring a 160 degrees F open and 140 degrees F close auto-reset limit device.

Installation Notes

A licensed HVAC technician should perform this replacement. Shut off all power to the furnace at the disconnect or breaker and allow the heat exchanger and plenum to cool fully before handling the switch. Verify the replacement setpoints match the original unit's wiring diagram before completing installation. Follow applicable local mechanical codes and the equipment manufacturer's service instructions.