OEM Carrier Transformer 40VA 120V to 24V for Model FC4DNF048000AAAA

This is the factory OEM replacement transformer (part number HT01CN241) for the Carrier FC4DNF048000AAAA fan coil unit. The transformer steps down 120V line voltage to the 24V AC signal required to power the control board, thermostat, and all low-voltage control circuit components. When the transformer fails, the entire control circuit goes dark — your thermostat will show no response, the system won't call for heating or cooling, and nothing will operate despite power being present at the unit.

• Specs: 120V primary | 24V secondary output | 40VA rating | OEM part number HT01CN241 | Factory-matched for Carrier FC4DNF048000AAAA fan coil
• OEM vs Generic: This OEM transformer is wound and rated to exact factory specifications, ensuring stable 24V output under full control-circuit load. Generic transformers frequently use undersized windings that sag under load, causing erratic thermostat behavior, nuisance lockouts, and premature control board failure.
• Install difficulty: 2/5 — Shut off all power to the unit before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter (to verify 24V output after install). Label or photograph all low-voltage wiring connections before disconnecting the old transformer.
• Warranty: 1-year OEM factory warranty against defects. Ships same business day from our stocked warehouse.

Compatibility: Engineered as a direct OEM replacement for Carrier model FC4DNF048000AAAA fan coil units. Always verify your existing transformer's primary voltage, secondary voltage, and VA rating against your unit's data plate before ordering. Our fitment team is available to confirm compatibility before you purchase — same-day shipping on all in-stock orders.