OEM Carrier Control Transformer 40VA 120V–24V for Model FX4DNF061000AAAA

This OEM replacement transformer (part# HT01CN241) is the factory-specified step-down transformer for the Carrier FX4DNF061000AAAA fan coil air handler. It converts 120V line voltage to the 24V AC signal that powers the control board, thermostat, and all low-voltage components in the system. When the transformer fails, the entire control circuit goes dead — the thermostat goes blank, the system refuses to respond to any call for heating or cooling, and no low-voltage components will energize. Replacing this small but critical part is often the fastest and most affordable way to restore full system operation.

• Specs: 40VA rating | Primary voltage: 120V AC | Secondary voltage: 24V AC | OEM part number HT01CN241 | Factory-matched for Carrier FX4DNF061000AAAA air handlers
• OEM vs Generic: This is a genuine OEM Carrier transformer built to exact factory VA and voltage specifications. Generic transformers may underperform on VA load capacity, causing nuisance trips of the control board's internal fuse or erratic thermostat behavior — especially in multi-stage or communicating systems.
• Install difficulty: 2/5 — Shut off all power to the unit before servicing. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to verify 24V output after install). Label all low-voltage wires before disconnecting from the secondary terminals.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Designed specifically for the Carrier FX4DNF061000AAAA fan coil air handler. Always verify your unit's control board requires a 40VA 24V secondary transformer by checking the data plate or existing transformer label before ordering. Our fitment team is available to confirm compatibility before you purchase — same-day shipping ensures you're back up and running fast.