OEM Carrier Control Transformer 40VA 120V/24V for Model FA4ANF048010AFAA

This OEM replacement transformer (part number HT01CN236) is the factory-specified step-down transformer for the Carrier FA4ANF048010AFAA air handler unit. The transformer converts 120V line voltage to the 24V AC signal that powers the entire control circuit — including the thermostat, control board, contactor coil, and zone controls. When this transformer fails, the result is complete control system shutdown: a blank thermostat, an unresponsive air handler, and no heating or cooling whatsoever. It is often one of the first components to check when the system appears totally dead despite confirmed line voltage at the unit.

• Specs: Input 120V AC | Output 24V AC | 40VA rating | OEM part number HT01CN236 | Factory-matched winding and insulation class for reliable low-voltage signal delivery
• OEM vs Generic: This is a genuine Carrier OEM transformer wound to exact factory VA ratings and insulation specs. Generic transformers often carry inconsistent VA output, which can cause nuisance tripping of the transformer's internal thermal fuse or unstable low-voltage control signals that lead to misdiagnosis of the control board.
• Install difficulty: 2/5 — Disconnect power at the breaker and verify with a multimeter before touching any wiring. Tools needed: flathead and Phillips screwdrivers, wire strippers, multimeter, needle-nose pliers. Label all wires before removal. The transformer mounts to the air handler cabinet with two screws and connects via quick-connect or screw terminals.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse — your repair stays on schedule.

Compatibility: Designed specifically for the Carrier FA4ANF048010AFAA fan coil / air handler unit. Always verify your existing transformer's input/output voltage and VA rating against your unit's data plate before ordering. Our HVAC parts specialists are available to confirm fitment before you buy — no guesswork required.