Fenwal 35-652505-003 Ignition Module

The Fenwal 35-652505-003 Ignition Module is a professional-grade, microprocessor-based Hot Surface Ignition (HSI) control designed specifically for Laars water heaters and boiler systems. As a critical component of the Fenwal 35-65 series, this module utilizes advanced logic to supervise the sequence of operation, including the inducer motor, pressure switch monitoring, and remote flame sensing. It features a field-selectable 120/240 VAC input, allowing for versatile installation across various equipment configurations without requiring multiple SKUs. With a 20-second prepurge/heat-up time and a 7-second trial for ignition (TFI), this control ensures precise timing and reliable combustion. The 35-652505-003 is engineered for high-demand HVACR environments, providing three ignition attempts before entering a lockout state to maintain system safety. Its quick-connect terminals and compact design make it a preferred OEM replacement part for technicians servicing WTR PIK LAARS units and similar hydronic heating applications.

Key Benefits for Contractors:

• Field-Selectable Voltage: Supports both 120V and 240V AC inputs, reducing the need to carry multiple ignition modules on the truck.
• Advanced Troubleshooting: Microprocessor control provides consistent timing and handles three ignition attempts without an automatic reset for better system diagnostics.
• Simplified Wiring: Features standard 1/4-inch quick-connect (QC) terminals for fast, secure electrical connections during field replacement.
• Enhanced Flame Supervision: Employs remote flame sensing technology to ensure the main burner is lit before allowing gas valve operation.
• Energy Efficiency: Designed to operate without full-time power, reducing standby energy consumption in gas-fired water heaters.

Common Technical Questions:

What are the specific timing specifications for the Fenwal 35-652505-003?
This module is programmed with a 20-second ignitor heat-up time and a 7-second trial for ignition. If a flame is not detected within the TFI, it will attempt ignition a total of three times before locking out.

Is the 35-652505-003 compatible with local or remote flame sensing?
This specific model is configured for remote flame sensing, requiring a separate flame rod to monitor the burner health and ensure safe operation.

Can I use this to replace other Fenwal 35-65 series modules?
Compatibility depends on the specific timing and TFI requirements of your appliance. Always verify the Fenwal 35-652505-003 specifications against the original equipment manufacturer (OEM) wiring diagram found on Laars water heaters.

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.