Fenwal 35-679932-551 Ignition Control

The Fenwal 35-679932-551 Ignition Control is a microprocessor-based 24 VAC Proven Hot Surface Ignition (HSI) module engineered for high-output commercial and industrial gas appliances exceeding 400,000 BTU. This Fenwal 35-67 series controller integrates a dedicated combustion blower relay with a 15A inducer fan rating, ensuring sequence-controlled ventilation via fixed 15-second pre-purge and 30-second post-purge cycles. Designed for direct replacesment ignition modules in rugged environments, the board features conformal coating for moisture resistance up to 95% RH. The system utilizes a single-try ignition sequence with a 4-second trial for ignition (TFI) and includes remote flame sensing capabilities. For field diagnostics, the unit incorporates an LED status indicator and accessible flame current test pins to verify microamp signals without breaking the circuit. It is built to meet ASME CSD-1 standards, making it a reliable choice for HVAC industrial heating controls using natural, LP, or manufactured gases.

• Enhanced System Safety: Integrated pressure switch monitoring ensuring the inducer fan is moving air before the HSI is energized.
• High Load Capacity: Robust relay ratings support 5.0A gas valves and 15A combustion blowers, eliminating the need for external secondary relays in many configurations.
• Precise Troubleshooting: On-board LED flash codes quickly identify pressure switch failures, flame losses, or internal hardware faults.
• Durable Construction: The Gray Noryl N-190 enclosure and conformal-coated circuitry provide stability in ambient temperatures ranging from -40°F to +165°F.
• Voltage Versatility: While the control circuit operates on 24 VAC, the line voltage compatibility extends to 120/240 VAC for hot surface ignitors.

What does a flashing LED on the Fenwal 35-679932-551 indicate?
The LED provides diagnostic codes; a steady on indicates internal failure, while specific flash sequences identify airflow faults or flame sensing issues. Always check the pressure switch and flame rod microamps first.

Can this module be used for multi-try ignition applications?
No, this specific model is a single-try ignition control. If the flame is not proven within the 4-second TFI, the system will enter a lockout state requiring a manual or power-cycle reset.

Is this control compatible with 120V or 240V ignitors?
Yes, the 35-679932-551 supports 24, 120, or 240 VAC hot surface ignitors depending on the line voltage supplied to the module's power input terminal.

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.