OEM Carrier Transformer 40VA 120V/24V for Model FA4CNF048000AAAA

This OEM replacement transformer (part# HT01CN241) is the factory-specified control circuit transformer for the Carrier FA4CNF048000AAAA air handler. It steps down 120V line voltage to the 24V signal voltage required by the thermostat, control board, contactor coil, and all other low-voltage components in the system. When this transformer fails, the entire control circuit goes dark — the thermostat becomes unresponsive, the system will not call for heating or cooling, and nothing runs. A failed transformer is often the first suspect when a system appears completely dead despite having power at the disconnect.

• Specs: 40VA rating | 120V primary / 24V secondary | OEM part number HT01CN241 | Factory-matched to Carrier FA4CNF048000AAAA air handler control circuit requirements
• OEM vs Generic: OEM transformers are wound and rated to exact factory VA specifications. Undersized or off-tolerance generic units can overheat under normal load, trip internal thermal fuses, and cause intermittent control failures that are difficult to diagnose.
• Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter (to confirm 24V output after install), wire nuts or spade connectors. Label and photograph all low-voltage wiring before disconnecting from the old transformer.
• Warranty: 1-year OEM factory warranty against defects in materials and workmanship. Orders placed by 3PM local time ship same business day from our HVAC-dedicated warehouse.

Compatibility: Designed specifically for the Carrier FA4CNF048000AAAA fan coil air handler. Always confirm the VA rating and primary/secondary voltages on your existing transformer's label before ordering to ensure a correct fit. If you're unsure of fitment, our parts team is available to verify compatibility before you buy — no guesswork required. In stock and ships today.