ICP Furnace Control Board Kit for RGS121LFCA0AAA — OEM Replacement | Ships Today

Overview

This OEM control board kit (part 1183618) is the integrated furnace control (IFC) that runs the entire heating sequence on the ICP Tempstar Heil RGS121LFCA0AAA gas furnace. The board manages the inducer, igniter, gas valve, and blower timing while continuously monitoring the limit and pressure safety switches and providing flame sensing and fault diagnostics. As the brain of the furnace, a failed control board produces some of the most disruptive symptoms: no response on a heat call, blower running constantly, intermittent ignition, or flashing diagnostic fault codes. Supplied as a complete kit, this exact-fit replacement restores proper sequencing, safety supervision, and diagnostic LED reporting.

Specifications

Compatibility

Designed for the ICP Tempstar Heil RGS121LFCA0AAA gas furnace and related RGS-series furnaces using this integrated control. Match the OEM part number and connector layout to your existing board before ordering.

Installation Guide

1. Safety First — Disconnect power at the furnace switch and breaker; verify zero voltage with a multimeter.
2. Access — Remove the furnace control/blower compartment panel.
3. Document — Photo every connector and wire location on the old board before disconnecting.
4. Remove — Unplug all harness connectors, remove the mounting screws, and lift out the failed board.
5. Install — Mount the new board and reconnect each harness to the matching terminal exactly per your photo.
6. Test — Restore power, run a full heat cycle, and confirm correct sequencing with no fault codes on the diagnostic LED.

Signs You Need a Replacement

• Furnace is completely unresponsive on a heat call
• Blower runs continuously or won't start
• Intermittent ignition or random short cycling
• Flashing fault/error codes on the board's diagnostic LED

Shipping & Returns

Ships same day before 3 PM CST. 30-day returns. National HVAC Parts fitment guarantee.