ICP Furnace Control Board Kit for RGS121LRCA0AAA — OEM 1183618 | Ships Today

Overview

This genuine OEM control board kit (part number 1183618) is the integrated furnace control (IFC) for the ICP / Tempstar / Heil RGS121LRCA0AAA gas furnace. The board is the brain of the system: it sequences the inducer, igniter, gas valve, and blower; monitors safety circuits (pressure switch, limit, flame sense); and flashes diagnostic fault codes. Control boards fail from power surges, heat stress, corroded relays, and cracked solder joints. A failed board can leave the furnace dead, stuck on the blower, or short-cycling on safety lockouts.

Specifications

Compatibility

Built for the ICP RGS121LRCA0AAA and other RGS121-platform gas furnaces sold under the ICP, Tempstar, and Heil brands. Match the board part number and connector layout to your existing control before installing.

Installation Guide

1. Safety First — Disconnect power and shut off gas. Verify zero voltage with a multimeter.
2. Access — Remove the furnace control-compartment service panel.
3. Document — Photograph every harness, plug, and DIP-switch / jumper setting on the old board.
4. Remove — Unplug all connectors, remove the mounting screws, and lift out the old board.
5. Install — Mount the new board, transfer any jumper/DIP settings, and reconnect each harness per your photos.
6. Test — Restore gas and power, run a full heat cycle, and confirm correct ignition, blower operation, and no fault codes.

Signs You Need a Replacement

• Furnace is completely unresponsive on a heat call
• Blower runs constantly or won't start
• Repeated lockouts with no underlying component fault
• Visible burnt relays, scorch marks, or no diagnostic LED

Shipping & Returns

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