Fenwal 35-655600-005 Control

The Fenwal 35-655600-005 is a professional-grade, microprocessor-based Hot Surface Ignition (HSI) control designed for reliable sequence management in 24VAC gas-fired appliances. Engineered for precision, this Fenwal ignition module features a single trial for ignition (1-try), 0-second pre-purge (0pp), and a 10-second trial for ignition (10sTFI) window. It is built to withstand the rigors of industrial and commercial environments, offering an operating temperature range of -40°F to +176°F. As a robust furnace control board replacement, it utilizes microprocessor ignition technology to provide repeatable timing for residential and commercial boiler ignition systems, water heaters, and pool heaters under 400K BTU. The unit includes on-board LED diagnostics to streamline troubleshooting for service technicians, ensuring rapid fault identification of airflow or flame sensing issues. Its compact, non-position-sensitive design allows for flexible mounting in space-constrained cabinets, maintaining a consistent flame sensing current of 0.7 microamps minimum for stable burner operation.

• Enhanced Reliability: Microprocessor-based logic ensures precise timing and consistent hot surface ignition sequences.
• Simplified Troubleshooting: Integrated diagnostic LED provides instant feedback on system status and fault conditions like lockout or erroneous flame signals.
• Broad Compatibility: Supports natural, LP, and manufactured gases, making it a versatile HVAC replacement part.
• Safe Operation: Features full-time flame sensing and safe-start checks to prevent hazardous conditions during the ignition cycle.
• Flexible Installation: Compact footprint and multi-angle mounting capability fit easily into existing control panels.

What does 10sTFI mean for this Fenwal control?
The 10sTFI (Trial For Ignition) is the 10-second window where the Fenwal 35-655600-005 energizes the gas valve to establish a flame. If the flame sensor does not detect a signal within this period, the module will enter a safety lockout.

How do I measure the flame current on this module?
Technicians can measure the flame strength by connecting a DC micro-ammeter to the FC+ and FC- test pins. A stable reading of 1.0 µA or higher is recommended for reliable operation, though the minimum threshold is 0.7 µA.

Can this replace a multi-try ignition module?
This specific model is a single trial for ignition (1-try) unit. If your system requires multiple attempts before lockout, you must verify that a 1-try sequence is compatible with your appliance’s safety certifications and BTU rating.

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.