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Tempstar Defrost Control Board for T4H448GKC100 — 24V Heat Pump Control | Ships Today
Tempstar

Tempstar Defrost Control Board for T4H448GKC100 — 24V Heat Pump Control | Ships Today

SKU: 1173636-GEN Brand: Tempstar

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Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

Overview

This is the OEM defrost control board (part number 1173636) for the Tempstar T4H448GKC100 heat pump. The defrost control board governs the unit's defrost cycle — monitoring outdoor coil temperature and run time to decide when to melt accumulated frost and ice during heating. It also sequences the reversing valve, compressor, and auxiliary heat. A failed board commonly causes a frozen outdoor coil, a heat pump stuck in one mode, short-cycling, or a unit that ignores the thermostat. This direct-fit 24V OEM replacement restores factory-correct defrost timing and system control.

Specifications

Spec Value
Part Number 1173636
Type Defrost Control Board
Brand Tempstar (ICP / Heil)
Control Voltage 24V
Fitment OEM, model-specific
For Model T4H448GKC100

Compatibility

Engineered for the Tempstar T4H448GKC100 heat pump and shared across ICP-family condensing units (Heil, Comfortmaker, Tempstar) that originally used board 1173636. Confirm the OEM number on your existing board before ordering.

Installation Guide

  1. Safety First — Disconnect power at the disconnect and breaker, then verify zero voltage at the board with a multimeter.
  2. Access — Remove the control-panel service cover on the outdoor unit.
  3. Document — Photograph every wire and connector position before disconnecting anything.
  4. Remove — Label and unplug the low-voltage harness and sensor leads, release the standoffs, and lift out the old board.
  5. Install — Seat the new board on the standoffs and reconnect every lead exactly as photographed, including the defrost sensor.
  6. Test — Restore power, run a heating cycle, and confirm defrost initiates and terminates correctly.

Signs You Need a Replacement

  • Outdoor coil ices over and never defrosts
  • Heat pump won't switch between heating and cooling
  • Compressor short-cycles or runs nonstop
  • No 24V output to the reversing valve or contactor

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

Frequently Asked Questions

Does this Control Board fit my Tempstar T4H448GKC100 — 24V Heat Pump Control | Ships Today?
Yes. This is the factory-specified OEM control board for the Tempstar T4H448GKC100 — 24V Heat Pump Control | Ships Today. It is a direct drop-in replacement that fits without modification. Always verify the model number on your equipment nameplate before ordering.
How do I replace the control board on my Tempstar T4H448GKC100 — 24V Heat Pump Control | Ships Today?
Difficulty: Advanced (1–2 hrs)
Step 1: Turn off breaker. Step 2: PHOTOGRAPH all wire connections before touching anything. Step 3: Label each wire with tape. Step 4: Disconnect all wires, remove old board. Step 5: Mount new board, reconnect all wires matching your photo exactly. Step 6: Restore power and test all modes. Exact part number match is critical.
My HVAC system is completely dead. What could be wrong?
Completely dead HVAC (no LED on board) = failed control board or blown fuse. Check board fuse first (3A or 5A, costs $1–$5). If fuse is good and board has power but no LED, board is dead. Always photograph wiring before replacing.
Is this control board compatible with Bryant or Payne too?
Many Tempstar parts are cross-compatible with Bryant and Payne since all three brands are manufactured by Carrier Global Corporation. The same physical part is often used across brand labels with different model numbers. To verify: check your Bryant or Payne equipment service manual for cross-compatible part numbers, or email info@nationalhvacparts.com with your model number.
Should I use OEM or aftermarket for my Tempstar control board?
OEM essential. Control boards are model-specific with precise firmware and connector layouts. Aftermarket boards rarely match all functions and can cause intermittent failures or safety issues. Always match the exact OEM part number.
How fast does National HVAC Parts ship?
Orders placed before 3:00 PM CST ship the same business day. Standard delivery is 2–5 business days anywhere in the continental United States. Express shipping available at checkout. We ship from Houston, TX to all 50 states. 30-day return policy on all parts.
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Mike Rivera
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