ICP Furnace Control Board Kit for RGS121LTCB0AAA — OEM 1183618 | Ships Today
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Overview
This OEM integrated furnace control (IFC) board kit is the brain of the ICP / Tempstar / Heil RGS121LTCB0AAA gas furnace. It manages the ignition sequence, inducer and blower timing, gas valve, flame sensing, and all safety lockouts. A failed board produces erratic behavior — blower that won't shut off, no ignition, short cycling, or a furnace that's completely dead despite good power. OEM part 1183618 ships as a kit with the correct connectors and mounting hardware to drop straight into the RGS121 control box.
Specifications
| Spec | Value |
|---|---|
| Part Number | 1183618 |
| Type | Integrated Furnace Control Board (kit) |
| Brand | ICP / Tempstar / Heil |
| Application | Single-stage gas furnace |
| Voltage | 120V primary / 24V control |
| Fit | OEM direct replacement |
Compatibility
Direct-fit replacement for the ICP Tempstar Heil RGS121LTCB0AAA furnace and ICP-family models that originally shipped with control board 1183618. Confirm your old board part number and connector layout before installing.
Installation Guide
- Safety First — Disconnect power at the furnace switch and breaker; verify zero voltage with a multimeter.
- Access — Remove the blower / control compartment service panel.
- Document — Photograph every wire and connector on the board before disconnecting anything.
- Remove — Unplug all harnesses, remove the mounting screws, and lift out the old board.
- Install — Mount the new 1183618 board, reconnect each harness exactly per your photo, and set any DIP switches to match the original.
- Test — Restore power, run a full heat cycle, and confirm proper ignition, blower timing, and no fault codes.
Signs You Need a Replacement
- Furnace completely dead with confirmed 120V supply.
- Blower runs continuously or won't start.
- No ignition sequence or random short cycling.
- Visible burns, corrosion, or blown components on the board.
Shipping & Returns
Ships same day before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.
Shipping Information
- Orders placed before 3PM CST ship same business day
- Standard delivery: 2-5 business days
- Express shipping available at checkout
- Free shipping on orders over $75
- Tracking number emailed upon shipment
Return Policy
- 30-day returns on unused parts in original packaging
- Electrical parts (capacitors, contactors, control boards) are final sale once installed
- Email info@nationalhvacparts.com to initiate a return
- Refunds processed within 5-7 business days