Tecumseh K71-108 Start Relay

The Tecumseh K71-108 Start Relay is a high-performance potential relay engineered specifically for single-phase compressor motor applications in industrial and commercial refrigeration units. This component acts as a critical electrical interface, utilizing Back Electromotive Force (BEMF) to engage the start capacitor and disconnect it once the rotor achieves approximately 75-80% of its rated operational speed. By managing the high-torque requirements of HVAC systems during the initial phase, the K71-108 relay prevents auxiliary winding burnout and ensures precise refrigeration parts synchronization for standard reciprocating compressors.

Designed for field durability, this start relay features a compact configuration that fits traditional control box layouts, making it a reliable compressor start relay replacement for Tecumseh-specific models and various industrial cooling setups. The normally closed (NC) contact design provides the necessary high-power boost to overcome initial motor resistance, optimizing startup cycles and reducing unnecessary mechanical stress on internal system components. For technicians performing HVAC compressor troubleshooting, this relay provides a consistent electrical snap-action that maintains optimal energy efficiency and prevents locked-rotor terminal scenarios in extreme operating environments.

• Ensures high-torque starting for residential and commercial compressors by efficiently managing start capacitor engagement.
• Reduces startup stress on windings, assisting in the longevity of the compressor motor's mechanical life.
• Maintains system energy efficiency by precisely disconnecting the start circuit at the correct BEMF threshold.
• Compatible with a wide range of Tecumseh refrigeration units and high-capacity HVAC systems.
• Durable housing designed to withstand the thermal and electrical demands of continuous duty cycles.

How do I know if the Tecumseh K71-108 is the correct replacement?
Confirm your compressor’s model number and electrical specifications. This potential relay is designed for single-phase motors requiring a high-start torque, typically used in HVAC and refrigeration applications where a 115V or specific voltage-rated potential relay is required.

What are the signs of a failing start relay?
Technicians frequently observe symptoms such as a humming sound without the compressor kicking in, frequent cycling of the overload protector, or the start winding staying in the circuit too long, which can lead to excessive heat and potential motor failure.

Can I test this relay with a multimeter?
Yes. Use a multimeter to check for continuity across the normally closed contacts (terminals 1 and 2). If you find an open circuit when the relay is unpowered, the component has failed and requires immediate replacement.

This item is not eligible for free shipping.

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.