ICP Furnace Control Board Kit for RGS121SRCB0AAA — OEM 1183618 | Ships Today

Overview

This is the OEM integrated furnace control board kit (part number 1183618) for the ICP / Tempstar / Heil RGS121SRCB0AAA gas furnace. The control board is the brain of the furnace — it manages the ignition sequence, monitors the flame sensor and pressure switches, sequences the inducer and blower motors, and protects the system through built-in safety lockouts. When this board fails, the furnace will not start, will short-cycle, or will lock out into a fault code. The kit ships with the replacement board and mounting hardware so you can restore reliable heating quickly.

Specifications

Compatibility

Engineered as a direct OEM replacement for the ICP, Tempstar, Heil, Comfortmaker and related brand RGS121SRCB0AAA gas furnace. Always confirm the part number printed on your existing board matches 1183618 before installing.

Installation Guide

1. Safety First — Disconnect power at the furnace switch and breaker, then verify zero voltage with a multimeter.
2. Access — Remove the furnace blower-compartment service panel.
3. Document — Photograph every wire and connector on the existing board before disconnecting anything.
4. Remove — Unplug the harness connectors, remove the mounting screws, and lift out the failed board.
5. Install — Mount the new board, then reconnect each harness exactly as photographed.
6. Test — Restore power and verify a full ignition and heating cycle, watching the diagnostic LED for fault codes.

Signs You Need a Replacement

• Furnace is completely dead with no diagnostic LED activity.
• Blower or inducer runs continuously or fails to start.
• Repeated ignition lockouts despite a good igniter and flame sensor.
• Visible scorching, burnt relays, or corrosion on the board.

Shipping & Returns

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