OEM Carrier Circuit Control Board HH680001 for Model U19X100U36B

This is the genuine OEM replacement circuit board (part number HH680001) for the Carrier U19X100U36B. The control board is the central command hub of your HVAC system — it orchestrates power distribution to every major component including the inducer motor, gas valve, igniter, blower motor, and flame sensor circuit. When this board fails, symptoms typically include a system that won't start, gets stuck in lockout mode, fires erratically, or shuts down immediately after ignition without an obvious mechanical cause. Before replacing the board, rule out simpler faults such as a tripped limit switch, failed igniter, or dirty flame sensor.

• OEM Part Number: HH680001 | Also replaces legacy part numbers 58GA680087, P771-1003, 75598, and 58GA75598 — verify your existing board's part number before ordering.
• OEM vs Generic: This is a factory-genuine Carrier board, not an aftermarket clone. OEM boards carry factory-calibrated firmware, correct terminal layouts, and are tested to Carrier's specifications — generic boards may introduce timing mismatches, nuisance lockouts, or voided equipment warranties.
• Install Difficulty: 4/5 — Control board replacement requires disconnecting and reconnecting multiple low- and line-voltage wiring harnesses. Photograph all wiring connections before removal. Tools needed: Phillips-head screwdriver, flathead screwdriver, needle-nose pliers, multimeter. Recommended for qualified HVAC technicians only; improper wiring can cause equipment damage or safety hazards.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Designed as the factory-specified control board for Carrier model U19X100U36B. Always verify your existing part number and match it to HH680001 before ordering. Questions about fitment? Our HVAC parts specialists confirm compatibility before you buy — contact us today and get your system back online fast.