Laars Heating Systems R0491300 Ignition Module

The Laars Heating Systems R0491300 Ignition Module is a critical microprocessor-based hot surface ignition control designed for precise combustion management in high-efficiency boilers and pool heaters. Formally cross-referenced and identical to the Fenwal 35-652933-115, this 24VAC HSI control module provides reliable trial-for-ignition (TFI) sequences with integrated safety timings, including a 15-second pre-purge and 15-second inter-purge. Engineered for technical reliability in demanding environments, it features Detect-A-Flame technology for sensitive flame rectification and a diagnostic LED to streamline HVAC troubleshooting. This module is a direct OEM replacement part for Laars Pennant, Neotherm, and Mighty Therm units, ensuring seamless ignition system compatibility without requiring field modifications. By monitoring the flame sensor signal with high precision, the R0491300 prevents nuisance lockouts and ensures the gas valve de-energizes immediately upon loss of flame. For contractors performing a boiler ignition repair, this unit offers the specialized 120/240 field-selectable line voltage support necessary for professional-grade heating system maintenance.

• Universal Compatibility: Direct substitute for Fenwal 35-652933-115, simplifying inventory for Laars and Jandy service calls.
• Advanced Diagnostics: Built-in LED provides instant fault code flashes for faster HVAC system inspection and reduced downtime.
• Robust Flame Sensing: Utilizes advanced microprocessor logic to maintain a stable flame rectification signal even in varying conditions.
• Safety-First Timings: Features factory-set purge cycles to clear the combustion chamber and ensure a safe trial for ignition.

Is the R0491300 compatible with older Jandy LRZE heaters?
Yes, this ignition control is the standard replacement for various Legacy pool heaters and Laars commercial boilers requiring a 24VAC HSI module.

How do I interpret the diagnostic LED codes?
A steady light indicates internal failure, while specific flash sequences help identify ignition lockouts or flame sense errors without a call for heat.

Does this module support remote flame sensing?
This ignition module supports both local and remote flame sensing configurations, providing flexibility for different burner assemblies.

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.