York S1-7975-3771 Relay

The York S1-7975-3771 is a professional-grade 24V SPDT Fan Relay designed for high-cycle reliability in residential and light commercial air handlers. For technicians troubleshooting blower motor sequencing or intermittent fan failures, this component provides the specific low-voltage logic required to switch high-amperage loads. This Single Pole Double Throw relay is the direct OEM replacement for legacy part numbers S1-6313-2271 and 134-20103-301D, ensuring a perfect physical fit and matched electrical characteristics. Built to withstand the back-EMF often seen in induction motor circuits, the internal contacts are engineered to prevent pitting and sticking, which is a common cause of fan-only operation issues. Whether you are managing a heating speed tap or a cooling call, this HVAC replacement part ensures the control board's signal is translated into precise mechanical action, maintaining the integrity of the system's airflow requirements and protecting the primary motor windings from improper sequencing.

• Universal Compatibility: Direct drop-in for York, Luxaire, and Coleman equipment using the S1-6313-2271 specification.
• SPDT Configuration: Offers both normally open (NO) and normally closed (NC) contacts for versatile wiring in multi-speed blower applications.
• Robust Coil Design: The 24V coil is designed to pull in even during slight voltage fluctuations common in busy peak-demand periods.
• Inductive Load Rating: Engineered specifically to handle the high inrush currents associated with furnace blower motors and heavy-duty fans.

Common Questions:

What are the signs that a York S1-7975-3771 needs replacement? If the indoor blower fails to start despite a call for cooling or if the fan runs continuously even when the thermostat is off, the internal contacts have likely failed or fused.

Can I use this relay to replace a 3-terminal SPST relay? Yes, you can use an SPDT relay to replace an SPST by identifying the common and the normally open (NO) terminals and leaving the normally closed (NC) terminal unused.

What is the primary function of the 24V coil in this relay? The coil acts as the electromagnetic trigger; when it receives 24V from the thermostat or control board, it creates a magnetic field that pulls the high-voltage contacts together to energize the blower motor.

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.