The Rheem-Ruud 425086 Sequencing Relay is a mission-critical 24V SPST N/O sequencing relay designed for precise load management in electric furnaces and air handlers. Engineered for high-duty cycles, this HVAC sequencing relay features a single pole single throw normally open configuration, ensuring staggered component activation to prevent circuit overloads during initial power-up. Field technicians rely on this OEM replacement relay for its specific make-and-break delay timings, typically rated at 25-80 seconds for "on" and 50-100 seconds for "off." These timings are essential for maintaining blower run-time once heating elements have de-energized, maximizing heat exchange efficiency. With a 24VAC coil and robust 25A resistive rating at 120/240V, the 425086 relay offers seamless integration into existing control circuits, making it the standard choice for restoring factory-spec furnace operation. Its flush-mount plate design allows for rapid installation in tight cabinet spaces, preventing downtime on service calls. Key Benefits for Contractors: Precise Timing Control: Factory-calibrated delays prevent simultaneous high-load activation, protecting the transformer and circuit breakers. High Current Capacity: Rated for up to 25A resistive loads, making it compatible with various Rheem-Ruud electric heat assemblies. Multi-Voltage Application: While triggered by a 24V coil, the contacts are rated for 120V, 230V, and 460V applications, providing versatility in the field. OEM Standards: Direct replacement for Rheem part 42-21279-08 and 8201-5615, ensuring mounting holes and terminal locations line up perfectly without modification. Common Questions: What does the delay-on feature accomplish? It allows heating elements to reach operational temperature before the blower starts, preventing the initial "cold blast" of air. Can this be used to replace a DPST relay? No, this SPST N/O relay only controls a single circuit. Verify your existing wiring diagram to ensure you do not need double-pole switching. How do I test the heater coil? Check for continuity across the 24V heater terminals. If the heater is open, the contacts will never transition to the closed position. 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.
