Reznor 122858 Limit Switch
The Reznor 122858 Limit Switch is a critical safety component designed for precise thermal regulation in Reznor unit heaters and makeup air systems. This 135F M/R Limit Switch serves as a primary high-limit safeguard, engineered to interrupt the electrical circuit if the burner inlet or discharge air temperature exceeds the fixed 135°F threshold. As a manual reset limit switch, it requires a physical inspection and manual intervention by a qualified technician before the heating cycle can resume, ensuring that underlying issues such as blower failure or obstructed airflow are addressed rather than bypassed by an automatic cycle.
Built with a durable TOD 60T14-2 style housing, this OEM Reznor replacement part is typically found in ADF and RDF series direct-fired units. For contractors, the 122858 temperature switch offers a drop-in fit with standard terminal connections, maintaining the original safety certifications of the appliance. Utilizing genuine HVAC replacement parts like the 122858 ensures that the high-limit protection remains calibrated to the manufacturer's exact thermal specifications, preventing heat exchanger damage and optimizing system reliability in demanding commercial environments.
Key Benefits- Fixed 135°F Trip Point: Provides accurate high-temperature cutoff to protect internal components from thermal stress.
- Manual Reset Safety: Prevents "nuisance" auto-cycling and forces a system check to identify dangerous operating conditions.
- OEM Compatibility: Specifically designed for Reznor ADF and RDF direct-fired heaters, ensuring perfect alignment and fit.
- Rugged Construction: Built for industrial use with high-grade materials to withstand frequent thermal cycling.
What causes the Reznor 122858 limit switch to trip?
Common causes include restricted return air, a failing blower motor, or dirty filters. Because this is a manual reset switch, you must depress the button on the back of the switch after the unit has cooled and the fault is cleared.
Can I replace an automatic reset switch with this manual reset model?
No, you should always replace a safety switch with the exact reset type and temperature rating specified by the manufacturer to maintain the unit's safety listing.
How do I verify if the 122858 switch has failed?
With power disconnected, check for continuity across the terminals. If the switch is cool and not tripped, it should show a closed circuit. An open circuit in a cool state indicates the switch needs to be reset or replaced.
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.
Reznor 122858 Limit Switch
The Reznor 122858 Limit Switch is a critical safety component designed for precise thermal regulation in Reznor unit heaters and makeup air systems. This 135F M/R Limit Switch serves as a primary high-limit safeguard, engineered to interrupt the electrical circuit if the burner inlet or discharge air temperature exceeds the fixed 135°F threshold. As a manual reset limit switch, it requires a physical inspection and manual intervention by a qualified technician before the heating cycle can resume, ensuring that underlying issues such as blower failure or obstructed airflow are addressed rather than bypassed by an automatic cycle.
Built with a durable TOD 60T14-2 style housing, this OEM Reznor replacement part is typically found in ADF and RDF series direct-fired units. For contractors, the 122858 temperature switch offers a drop-in fit with standard terminal connections, maintaining the original safety certifications of the appliance. Utilizing genuine HVAC replacement parts like the 122858 ensures that the high-limit protection remains calibrated to the manufacturer's exact thermal specifications, preventing heat exchanger damage and optimizing system reliability in demanding commercial environments.
Key Benefits- Fixed 135°F Trip Point: Provides accurate high-temperature cutoff to protect internal components from thermal stress.
- Manual Reset Safety: Prevents "nuisance" auto-cycling and forces a system check to identify dangerous operating conditions.
- OEM Compatibility: Specifically designed for Reznor ADF and RDF direct-fired heaters, ensuring perfect alignment and fit.
- Rugged Construction: Built for industrial use with high-grade materials to withstand frequent thermal cycling.
What causes the Reznor 122858 limit switch to trip?
Common causes include restricted return air, a failing blower motor, or dirty filters. Because this is a manual reset switch, you must depress the button on the back of the switch after the unit has cooled and the fault is cleared.
Can I replace an automatic reset switch with this manual reset model?
No, you should always replace a safety switch with the exact reset type and temperature rating specified by the manufacturer to maintain the unit's safety listing.
How do I verify if the 122858 switch has failed?
With power disconnected, check for continuity across the terminals. If the switch is cool and not tripped, it should show a closed circuit. An open circuit in a cool state indicates the switch needs to be reset or replaced.
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.
Product Information
Product Information
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Shipping & Returns
Description
The Reznor 122858 Limit Switch is a critical safety component designed for precise thermal regulation in Reznor unit heaters and makeup air systems. This 135F M/R Limit Switch serves as a primary high-limit safeguard, engineered to interrupt the electrical circuit if the burner inlet or discharge air temperature exceeds the fixed 135°F threshold. As a manual reset limit switch, it requires a physical inspection and manual intervention by a qualified technician before the heating cycle can resume, ensuring that underlying issues such as blower failure or obstructed airflow are addressed rather than bypassed by an automatic cycle.
Built with a durable TOD 60T14-2 style housing, this OEM Reznor replacement part is typically found in ADF and RDF series direct-fired units. For contractors, the 122858 temperature switch offers a drop-in fit with standard terminal connections, maintaining the original safety certifications of the appliance. Utilizing genuine HVAC replacement parts like the 122858 ensures that the high-limit protection remains calibrated to the manufacturer's exact thermal specifications, preventing heat exchanger damage and optimizing system reliability in demanding commercial environments.
Key Benefits- Fixed 135°F Trip Point: Provides accurate high-temperature cutoff to protect internal components from thermal stress.
- Manual Reset Safety: Prevents "nuisance" auto-cycling and forces a system check to identify dangerous operating conditions.
- OEM Compatibility: Specifically designed for Reznor ADF and RDF direct-fired heaters, ensuring perfect alignment and fit.
- Rugged Construction: Built for industrial use with high-grade materials to withstand frequent thermal cycling.
What causes the Reznor 122858 limit switch to trip?
Common causes include restricted return air, a failing blower motor, or dirty filters. Because this is a manual reset switch, you must depress the button on the back of the switch after the unit has cooled and the fault is cleared.
Can I replace an automatic reset switch with this manual reset model?
No, you should always replace a safety switch with the exact reset type and temperature rating specified by the manufacturer to maintain the unit's safety listing.
How do I verify if the 122858 switch has failed?
With power disconnected, check for continuity across the terminals. If the switch is cool and not tripped, it should show a closed circuit. An open circuit in a cool state indicates the switch needs to be reset or replaced.
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.
