Tempstar Defrost Control Board for T4H324GKA100 — OEM 1173636 Heat Pump Board | Ships Today
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Overview
This is a genuine OEM defrost control board (part number 1173636) for the Tempstar T4H324GKA100 heat pump condensing unit. The defrost control board is the brain of the heat pump's defrost cycle — it monitors the outdoor coil temperature and accumulated run time, then commands the system to reverse into a temporary cooling cycle to melt frost and ice off the outdoor coil during winter operation. It coordinates the reversing valve, condenser fan, and compressor timing to keep the unit running efficiently. When this board fails, the outdoor coil can ice over completely, heating capacity drops, and the compressor may short-cycle or lock out on a fault. Operating on 24V control logic, this board is a direct factory replacement.
Specifications
| Spec | Value |
|---|---|
| Part Number | 1173636 |
| Type | Defrost Control Board |
| Brand | Tempstar (ICP/Heil) |
| Control Voltage | 24V |
| Application | Heat Pump Defrost Cycle |
| Fitment | OEM Direct Replacement |
Compatibility
Designed as a direct-fit OEM replacement for the Tempstar T4H324GKA100 heat pump. The 1173636 board is also used across many ICP-family (Tempstar, Heil, Comfortmaker, Arcoaire) heat pump models that share this control platform. Always verify your existing board's part number before ordering.
Installation Guide
- Safety First — Disconnect power at the outdoor disconnect and verify zero voltage with a multimeter before touching any wiring.
- Access — Remove the condenser unit's control-panel access cover.
- Document — Photograph every wire and terminal connection on the existing board before disconnecting anything.
- Remove — Label and disconnect the low-voltage and sensor leads, release the board's mounting standoffs or screws, and lift out the old board.
- Install — Mount the new 1173636 board, then reconnect each lead exactly as shown in your photos. Reconnect the defrost thermostat/sensor.
- Test — Restore power and confirm normal heating operation; force or wait for a defrost cycle to verify the board commands it correctly.
Signs You Need a Replacement
- Outdoor coil freezes or ices over and never defrosts
- Heat pump fails to switch to defrost or stays in defrost too long
- Compressor short-cycles or locks out during heating mode
- Visible burn marks, corrosion, or scorched 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