Lochinvar & A.O. Smith 100208494 Control Board

Secure the operational integrity of high-efficiency heating systems with the Lochinvar & A.O. Smith 100208494 Main Control Board. This genuine OEM component is the primary ignition control module designed to manage critical firing sequences, blower speed modulation, and pump logic for the Lochinvar Knight boiler series and compatible A.O. Smith commercial water heaters manufactured before serial 1707. As a direct replacement for the discontinued RLY2100 and RLY2100K, this board integrates seamlessly into the existing SMART SYSTEM architecture without requiring field modifications. It processes data from temperature sensors and the air pressure switch to regulate the combustion blower and gas valve, ensuring precise thermal output and condensing efficiency. For technicians troubleshooting "no display" or communication errors, this 100208494 replacement part provides the necessary hardware reliability to restore DHW priority and space heating functionality. Verify your unit's serial number to ensure compatibility with this specific HVAC control board revision.

Key Benefits

• Direct OEM Compatibility: Serves as the exact successor to RLY2100 and RLY2100K, maintaining original factory specifications.
• Enhanced System Logic: Orchestrates complex Lochinvar Knight firing sequences, including blower modulation and multi-pump control.
• Precision Diagnostics: Designed for integration with the SMART SYSTEM digital display for rapid error code reporting and system status monitoring.
• Commercial Grade Build: Engineered to withstand the thermal demands of high-recovery commercial water heating and condensing boiler applications.

Common Questions

Does this board require a software flash upon installation?

While the board comes pre-programmed with standard logic, technicians should review the installer parameters to match the specific model and firing rate of the unit being serviced.

Is this the correct board for Knight boilers with serial numbers after 1707?

No, this specific part number is generally utilized for units produced before serial 1707. Always cross-reference the manufacturer part list for newer production runs.

What does it mean if the board is identical to RLY2100K?

The "K" often designated a kit version in legacy systems, but the 100208494 is the current standardized part number for the core Main Control Board assembly.

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.