Supco SHL506 Limit Switch
The Supco SHL506 Limit Switch is a high-performance HVAC furnace limit control engineered for precise thermal protection in residential and commercial heating systems. This plenum thermostat features a fixed open temperature of 170°F and a fixed close temperature of 130°F, providing a reliable 40°F differential to prevent heat exchanger overheating. With its SPST normally closed circuit and auto reset functionality, the SHL506 ensures seamless operation without the need for manual intervention after a high-limit event. Designed with a 1.87-inch insertion length and a board-mounted configuration, it serves as a thermodisc L170-40 style replacement, making it a critical component for maintaining system safety and efficiency. As a direct cross for 87H91, this bimetal control is also compatible with various OEM specifications from manufacturers like Lennox, Bryant, and Trane, offering versatile application across multiple furnace models.
Key Benefits- Precise Thermal Regulation: Fixed 170°F opening point ensures the burner shuts down immediately if plenum temperatures exceed safe operating limits.
- Broad Compatibility: Serves as a direct cross for 87H91, 47-25349-02, and HH12ZB170, reducing the need for carrying multiple specialized SKUs.
- Durable Construction: Features a 1/2-inch bimetal sensing element for consistent response times and long-term reliability in high-cycle environments.
- Efficiency: Automatic reset allows the system to resume heating once temperatures drop to 130°F, minimizing downtime for the end user.
What does it mean when a limit switch is "normally closed"?
In HVAC applications, a normally closed switch like the SHL506 maintains a completed circuit to the gas valve or controller during standard operation. It only opens the circuit to cut power when the 170°F threshold is reached.
Can I use this as a replacement for a 1.87-inch 87H91 switch?
Yes, the Supco SHL506 is specifically designed as a direct technical cross-reference for the 87H91, maintaining the same insertion depth and thermal parameters.
How do I know if my furnace limit switch has failed?
If your furnace blower runs continuously while the burners fail to ignite, or if the system short cycles, the plenum limit control may be stuck open or out of calibration, requiring a replacement to restore safe operation.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
Original: $15.87
-65%$15.87
$5.55Supco SHL506 Limit Switch
The Supco SHL506 Limit Switch is a high-performance HVAC furnace limit control engineered for precise thermal protection in residential and commercial heating systems. This plenum thermostat features a fixed open temperature of 170°F and a fixed close temperature of 130°F, providing a reliable 40°F differential to prevent heat exchanger overheating. With its SPST normally closed circuit and auto reset functionality, the SHL506 ensures seamless operation without the need for manual intervention after a high-limit event. Designed with a 1.87-inch insertion length and a board-mounted configuration, it serves as a thermodisc L170-40 style replacement, making it a critical component for maintaining system safety and efficiency. As a direct cross for 87H91, this bimetal control is also compatible with various OEM specifications from manufacturers like Lennox, Bryant, and Trane, offering versatile application across multiple furnace models.
Key Benefits- Precise Thermal Regulation: Fixed 170°F opening point ensures the burner shuts down immediately if plenum temperatures exceed safe operating limits.
- Broad Compatibility: Serves as a direct cross for 87H91, 47-25349-02, and HH12ZB170, reducing the need for carrying multiple specialized SKUs.
- Durable Construction: Features a 1/2-inch bimetal sensing element for consistent response times and long-term reliability in high-cycle environments.
- Efficiency: Automatic reset allows the system to resume heating once temperatures drop to 130°F, minimizing downtime for the end user.
What does it mean when a limit switch is "normally closed"?
In HVAC applications, a normally closed switch like the SHL506 maintains a completed circuit to the gas valve or controller during standard operation. It only opens the circuit to cut power when the 170°F threshold is reached.
Can I use this as a replacement for a 1.87-inch 87H91 switch?
Yes, the Supco SHL506 is specifically designed as a direct technical cross-reference for the 87H91, maintaining the same insertion depth and thermal parameters.
How do I know if my furnace limit switch has failed?
If your furnace blower runs continuously while the burners fail to ignite, or if the system short cycles, the plenum limit control may be stuck open or out of calibration, requiring a replacement to restore safe operation.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
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Description
The Supco SHL506 Limit Switch is a high-performance HVAC furnace limit control engineered for precise thermal protection in residential and commercial heating systems. This plenum thermostat features a fixed open temperature of 170°F and a fixed close temperature of 130°F, providing a reliable 40°F differential to prevent heat exchanger overheating. With its SPST normally closed circuit and auto reset functionality, the SHL506 ensures seamless operation without the need for manual intervention after a high-limit event. Designed with a 1.87-inch insertion length and a board-mounted configuration, it serves as a thermodisc L170-40 style replacement, making it a critical component for maintaining system safety and efficiency. As a direct cross for 87H91, this bimetal control is also compatible with various OEM specifications from manufacturers like Lennox, Bryant, and Trane, offering versatile application across multiple furnace models.
Key Benefits- Precise Thermal Regulation: Fixed 170°F opening point ensures the burner shuts down immediately if plenum temperatures exceed safe operating limits.
- Broad Compatibility: Serves as a direct cross for 87H91, 47-25349-02, and HH12ZB170, reducing the need for carrying multiple specialized SKUs.
- Durable Construction: Features a 1/2-inch bimetal sensing element for consistent response times and long-term reliability in high-cycle environments.
- Efficiency: Automatic reset allows the system to resume heating once temperatures drop to 130°F, minimizing downtime for the end user.
What does it mean when a limit switch is "normally closed"?
In HVAC applications, a normally closed switch like the SHL506 maintains a completed circuit to the gas valve or controller during standard operation. It only opens the circuit to cut power when the 170°F threshold is reached.
Can I use this as a replacement for a 1.87-inch 87H91 switch?
Yes, the Supco SHL506 is specifically designed as a direct technical cross-reference for the 87H91, maintaining the same insertion depth and thermal parameters.
How do I know if my furnace limit switch has failed?
If your furnace blower runs continuously while the burners fail to ignite, or if the system short cycles, the plenum limit control may be stuck open or out of calibration, requiring a replacement to restore safe operation.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
