Tempstar Control Board for T4A336GKD100 – Comfort Alert Diagnostics | Ships Today

Overview

This is the genuine OEM Comfort Alert control board (part #1177402) for the Tempstar T4A336GKD100 heat pump condensing unit. The Comfort Alert module monitors compressor and contactor operation, supply voltage, and run-time faults, then reports them through an onboard status LED so a technician can quickly diagnose locked-rotor, open-circuit, low-voltage, and other faults. When this board fails, the unit may not start, short-cycle, lose its protective lockouts, or stop reporting diagnostic codes.

Specifications

Compatibility

Engineered for the Tempstar T4A336GKD100 heat pump and shared across many ICP-built T4A3 series units sold under the Tempstar, Heil, Comfortmaker, and ICP brands. Confirm the printed part number on your existing board reads 1177402 before ordering.

Installation Guide

1. Safety First – Disconnect power at the outdoor disconnect and verify zero voltage with a multimeter before handling any wiring.
2. Access – Remove the condenser control panel cover to expose the existing board.
3. Document – Photograph every wire and terminal connection before disconnecting anything.
4. Remove – Label and unplug the low-voltage and line connections, then unsnap or unscrew the old board from its standoffs.
5. Install – Mount the new 1177402 board, reconnect each wire exactly as photographed, and confirm the harness is seated.
6. Test – Restore power, watch the status LED for a normal boot, and verify the unit starts and runs without fault codes.

Signs You Need a Replacement

• Outdoor unit will not start or randomly short-cycles.
• Status LED is dark, flashing erratically, or stuck on a fault code.
• Compressor or contactor will not energize on a valid call.
• Loss of protective lockouts (low voltage, locked rotor, etc.).

Shipping & Returns

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