Fenwal 35-615526-223 Control

The Fenwal 35-615526-223 is a microprocessor-based 24V Direct Spark Ignition (DSI) control engineered for precision combustion management in residential and commercial gas-fired equipment. This Fenwal ignition module features a 3-try ignition sequence, providing multiple attempts to establish a flame before entering a safety lockout, which significantly reduces nuisance service calls in cold-start or high-altitude environments. Designed with a 30-second pre-purge and 120/240V inducer blower relay support, it ensures the combustion chamber is cleared of residual gases for a safe, reliable startup every cycle.

For technicians troubleshooting complex HVAC furnace controls, the 35-615526-223 includes integrated LED diagnostics to quickly identify system faults such as airflow failure or flame loss. The 7-second Trial for Ignition (TFI) window and remote flame sensing capabilities allow for flexible mounting and high-sensitivity monitoring (0.7 µA minimum). This Fenwal DSI control is a robust solution for maintaining high-efficiency performance in boilers, water heaters, and standard gas furnaces.

Key Benefits

• Optimized Safety: The 30-second post-purge and pre-purge cycles ensure clean combustion and prevent delayed ignition.
• Enhanced Reliability: The 3-try ignition logic provides redundant startups to maintain uptime in demanding conditions.
• Simplified Testing: Built-in flame current test pins allow for immediate signal strength verification without breaking the circuit.
• Versatile Application: Supports both local and remote flame sense configurations to fit various burner geometries.
• Durable Construction: Conformal-coated circuitry protects the microprocessor control against moisture and industrial contaminants.

Common Questions

What do the LED flash codes mean on the Fenwal 35-615526-223?
The onboard LED provides specific pulse patterns to indicate system status. A steady light typically indicates internal board health, while specific flashes point to issues like "Airflow Fault," "Flame Sanity Check," or "Ignition Lockout" after three failed attempts.

Can this module replace a single-try ignition control?
Yes, provided the voltage (24VAC) and timing requirements (7s TFI/30s Purge) align with the appliance manufacturer’s specifications. Moving to a 3-try system like this often improves reliability in systems prone to ignition delays.

What is the minimum flame current required for operation?
The module requires a minimum flame signal of 0.7 microamps (µA). If the signal drops below this threshold, the control will de-energize the gas valve to ensure safety.

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.