OEM Carrier 40VA Control Transformer for Model FB4ANB060000AFAA

This is the factory OEM replacement transformer (part number HT01CN236) for the Carrier FB4ANB060000AFAA fan coil air handler. The transformer steps down 120V line voltage to 24V AC to power the low-voltage control circuit — including your thermostat, contactor coil, and control board. When this transformer fails, the entire control circuit goes dead: the thermostat goes blank, the system won't respond to any commands, and nothing turns on. A failed transformer is often misdiagnosed as a bad control board, making this an essential first diagnostic check.

• Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01CN236 | Direct plug-in replacement with factory wiring harness compatibility
• OEM vs Generic: This OEM unit is wound to exact factory VA ratings, ensuring stable 24V output under full control circuit load. Undersized or off-tolerance generic transformers can cause nuisance lockouts, erratic thermostat behavior, and premature contactor coil failure.
• Install difficulty: 2/5 — Disconnect power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to verify 24V output after install). Label or photograph existing wiring before disconnecting. The transformer typically mounts inside the air handler cabinet on the control board bracket.
• Warranty: 1-year OEM factory warranty against defects. Orders placed before cutoff ship same business day from our warehouse.

Compatibility: Designed specifically for the Carrier FB4ANB060000AFAA fan coil air handler. Always verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate or control board wiring diagram before ordering. If you're unsure of fitment, our HVAC parts specialists are available to confirm compatibility before you buy — no guesswork required.