York S1-025-29041-005 Limit Switch

For contractors servicing York and Coleman heating equipment, the York S1-025-29041-005 Limit Switch is a critical OEM replacement part designed for high-limit temperature monitoring. This auto-reset limit control is engineered with a 3-inch insert (3" stem) and features a specific thermal profile where the contacts open at 140°F and automatically close at 110°F. If you are troubleshooting a furnace short cycling or encountering a 4 red light flash code on a PV8 variable speed gas furnace or a TG9S model, this high-limit switch ensures the burner circuit is interrupted if plenum temperatures exceed safe operational thresholds.

Built as a genuine replacement for outdated or failed L140-30 limit switches, this component is essential for maintaining HVAC system safety and thermal regulation. The bimetal disc sensor provides reliable automatic reset functionality, allowing the unit to resume operation once the internal heat exchanger temperature drops back to 110°F. As a veteran HVAC technician, you know that using OEM York parts prevents the common compatibility issues found with generic HVAC limit sensors, especially regarding exact insertion depth and snap-action response times.

Key Benefits

• Precision Thermal Calibration: 140°F opening and 110°F closing points prevent heat exchanger damage and promote safe operation.
• Direct OEM Fit: Guaranteed compatibility with York, Coleman, and Luxaire condensing furnaces, including 2-stage upflow and horizontal variable speed models.
• Enhanced Durability: Robust construction designed for high-cycle applications in residential HVAC environments.
• Simplified Field Replacement: Standard 3-inch insertion length and mounting plate dimensions ensure a drop-in replacement for part number 17534 and 42324.

Common Questions

Why is my furnace flashing a 4-light code?
This usually indicates an open high-limit circuit. While the S1-025-29041-005 may be faulty, always check for airflow restrictions like dirty filters, blocked returns, or a failing blower motor first.

Can I use this for a 150°F application?
No. This switch is specifically calibrated for 140°F. Substituting with a higher limit can bypass critical safety protections for the heat exchanger.

Is this an automatic or manual reset switch?
This is an automatic limit switch, meaning it will reset itself once the temperature falls below the 110°F threshold.

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.