OEM Carrier Transformer 40VA 120V/24V for Model FX4DNF037L10ACAA

This OEM replacement transformer (part number HT01CN241) is the factory-specified control circuit transformer for the Carrier FX4DNF037L10ACAA fan coil air handler. The transformer steps down 120V line voltage to the 24V AC signal that powers the thermostat circuit, control board, and all low-voltage safety controls. When the transformer fails, the entire control circuit loses power — the thermostat goes blank, the system won't respond to any call for heating or cooling, and no status LEDs illuminate on the control board. In some cases, a failed transformer is caused by a short elsewhere in the low-voltage wiring, so inspect all 24V wiring and components before replacement.

• Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM Part Number: HT01CN241 | Factory-matched output voltage and VA capacity for full control circuit compatibility
• OEM vs Generic: This OEM transformer is wound and tested to Carrier's exact tolerances, ensuring stable 24V output under full load. Generic transformers may deliver inconsistent voltage that can damage sensitive control boards or cause nuisance lockouts.
• Install Difficulty: 2/5 — Disconnect power at the breaker before beginning any work. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Note wire colors and terminal positions before removing the old unit. Verify 24V output with a multimeter after installation before restoring low-voltage wiring.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier FX4DNF037L10ACAA fan coil air handler. Always verify the VA rating and primary/secondary voltages against your unit's data plate before ordering. If you need fitment confirmation, our HVAC parts specialists are available to verify compatibility before you buy — same-day shipping on all in-stock orders.