Fenwal 35-605506-227 Control

The Fenwal 35-605506-227 is a microprocessor-based 24V Direct Spark Ignition (DSI) control engineered for precision timing and reliable flame supervision in gas-fired atmospheric and power-vented heating systems. This veteran-grade module features a 30-second pre-purge cycle to clear the combustion chamber of residual gases prior to ignition, ensuring a safe start-up sequence every time. Designed with a 15-second Trial for Ignition (TFI) and a 3-try ignition logic, the 35-605506-227 provides robust performance for systems running on natural, LP, or manufactured gases, attempting multiple cycles to establish a flame before entering a safety lockout.

Built for the rigors of field service, this Fenwal ignition module supports both local and remote flame sensing (RemSen), offering HVAC contractors the flexibility needed for various burner configurations. The DETECT-A-FLAME technology ensures high-sensitivity flame monitoring (0.7 µA minimum), reducing nuisance lockouts in demanding environments. Troubleshooting is streamlined via on-board diagnostic LEDs that provide specific flash codes for internal failures, airflow faults, or ignition lockouts. With a wide operating temperature range of -40°F to 176°F and a conformal-coated circuit board for moisture resistance, this DSI gas ignition control is a reliable drop-in solution for commercial cooking equipment, unit heaters, and water heaters requiring 24 VAC input.

Key Benefits

• Advanced Microprocessor Logic: Delivers precise 30-second pre-purge and 15-second TFI timings for repeatable combustion control.
• Multi-Try Reliability: The 3-try sequence minimizes system downtime by attempting three ignition cycles before requiring a manual or automatic reset.
• Diagnostic Capability: Integrated LED indicators significantly reduce diagnostic time by identifying fault modes like low voltage or flame signal loss.
• Flexible Sensing: Compatible with remote flame sensors or local sense electrodes to match diverse appliance requirements.
• Rugged Construction: Conformal coating protects against non-condensing humidity up to 95% R.H., ideal for mechanical rooms.

Common Questions

How do I test the flame signal on this module?
Use a DC microammeter connected to the FC+ and FC- terminals. A stable reading of 0.7 µA or higher is required to maintain the gas valve circuit. If the reading is lower, check for dirty electrodes or poor burner grounding.

Can this unit replace a single-try DSI control?
Yes, provided the voltage (24 VAC) and timing requirements (30PP/15TFI) align with the appliance manufacturer's specifications. The 3-try logic provides additional attempts which can improve reliability in older systems.

What does a steady-on LED signify?
A steady-on LED typically indicates an internal control module failure or a software error. Before replacing the unit, cycle the 24V power to see if the microprocessor resets to a normal operating state.

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.