Lochinvar & A.O. Smith 100208511 Prepurge Relay

The Lochinvar & A.O. Smith 100208511 Prepurge Relay is a mission-critical 24VAC control component engineered for high-efficiency gas-fired boilers and commercial water heaters. This relay is essential for managing the initial combustion system pre-purge cycle, ensuring that any residual unburned fuel is safely cleared from the combustion chamber before the ignition sequence begins. Designed with 10 Amp contact ratings at 50/60Hz, the 100208511 provides precise timing and reliable switching for safety-limit strings and blower motor circuits. As a direct replacement for the RLY2714 and RLY2714K, this OEM prepurge relay offers drop-in compatibility with an extensive range of Lochinvar Power-Fin and Copper-Fin models, including the 250-1000 and 401-2071 series. For field technicians troubleshooting intermittent ignition failures or blower stalling issues, this 24 volt HVAC relay is the industry standard for maintaining system integrity and meeting strict NOx emission performance standards through optimized airflow management.

• OEM Compatibility: Seamlessly replaces 100208511, RLY2714, and RLY2714K in Lochinvar and A.O. Smith equipment.
• Enhanced Safety: Automates the mandatory pre-purge cycle to prevent hazardous delayed ignition events.
• Heavy-Duty Construction: Rated for 10A at 24VAC, providing robust switching capacity for commercial inducer motors.
• Precision Timing: Ensures optimal combustion conditions, contributing to higher fuel efficiency and reduced mechanical stress.

Is the 100208511 compatible with RLY2714 systems?
Yes, the 100208511 is the current manufacturer-designated replacement and is functionally identical to the RLY2714 and RLY2714K versions.

What are the symptoms of a failing prepurge relay?
Technicians typically observe the inducer motor failing to initiate, or the ignition sequence timing out because the 24VAC signal is not completing the circuit to the gas valve.

Does this relay require a specific mounting orientation?
While it follows standard HVAC relay footprints, it should be secured firmly within the control cabinet to prevent vibration-induced contact bounce.

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.