Fenwal 35-665938-215 Control Board

The Fenwal 35-665938-215 is a robust 120/240V Hot Surface Ignition (HSI) control board designed for precise automatic ignition system management in commercial and industrial HVACR applications. This microprocessor-based gas ignition control provides consistent 120V HSI trial for ignition, utilizing remote flame sensing technology to ensure safe burner operation. Engineered for versatility, this Fenwal 35 series model handles line voltage requirements while maintaining a compact footprint for streamlined field replacement. It is a critical component for technicians troubleshooting intermittent ignition issues or failed hot surface igniter sequences. By monitoring the flame signal and managing gas valve timing, this board prevents unsafe gas accumulation and optimizes combustion cycles. Whether you are performing a furnace control board replacement or servicing a boiler, the 35-665938-215 ensures reliable flame rectification and logic sequencing for demanding heating environments.

• Dual Voltage Compatibility: Operates on 120/240V AC power supplies, providing flexibility for various equipment configurations.
• Advanced Diagnostics: Built-in logic facilitates faster troubleshooting of ignition failures and flame lockout conditions.
• Precise Timing: Factory-set timings for prepurge and ignition trials ensure adherence to manufacturer specifications.
• Reliable Flame Sensing: High-sensitivity remote sensing prevents nuisance shutdowns while maintaining strict safety standards.
• Direct Fit Replacement: Lightweight 0.50 lbs design allows for easy installation in tight control cabinets.

What are the technical differences between this and a standard 24V control?
Unlike residential 24V units, the Fenwal 35-665938-215 is designed to handle 120/240V line voltage directly, making it suitable for larger commercial burners and specific hot surface ignition hardware that requires higher power input.

Does this board support local or remote flame sensing?
This specific model is engineered for remote flame sensing, requiring a separate flame rod to monitor the combustion process via flame rectification back to the microprocessor.

Can this be used to replace older 35-66 series boards?
Compatibility depends on the specific suffix and timing requirements of the appliance. Always verify the MPN 35-665938-215 and voltage ratings against the wiring diagram of the unit under service.

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.