OEM Carrier Circuit Control Board HH680001 for Model UPFLOW100U4819A

This is the genuine OEM Carrier circuit board (part number HH680001), the factory-specified replacement for the Carrier UPFLOW100U4819A upflow gas furnace. The integrated furnace control (IFC) board is the operational brain of your heating system — it sequences ignition, manages blower fan timing, monitors safety inputs from pressure switches and limit controls, and communicates status to your thermostat. When this board fails, you may experience complete system shutdown, failure to ignite, erratic blower behavior, or a furnace that starts a heating cycle but immediately locks out. Fault LED codes on the board itself are the fastest path to diagnosis.

• Specs: OEM Part Number HH680001 | Cross-reference: 0854680 | Application: Upflow gas furnace control board | Compatible voltage: 120V/24V control circuit | Multi-stage diagnostic LED fault codes
• OEM vs Generic: This is a genuine Carrier OEM board — not an aftermarket substitute. OEM boards carry exact firmware, relay ratings, and terminal configurations engineered for your specific unit. Generic boards risk mis-sequencing ignition or misreading safety inputs, which can cause nuisance lockouts or, worse, unsafe operation.
• Install Difficulty: 3/5 — Disconnect power and gas before beginning. Photograph all wiring harness connections before removal. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, smartphone (for wiring photos), multimeter to confirm 24V control circuit is intact post-install. A qualified HVAC technician is recommended for this repair.
• Warranty: 1-year OEM factory warranty. In stock — ships same business day from our warehouse when ordered before cutoff.

Compatibility: Designed as a direct OEM replacement for the Carrier UPFLOW100U4819A upflow gas furnace. Verify your existing board's part number (HH680001 or cross-reference 0854680) against your unit's data plate before ordering. Not sure it fits? Our HVAC parts specialists verify fitment before every order — contact us before you buy.