OEM Carrier Control Transformer 40VA 120V to 24V for Model FX4CNF018T00AAAA

This is the factory OEM replacement transformer (part number HT01CN241) for the Carrier FX4CNF018T00AAAA fan coil air handler. The transformer steps down 120V line voltage to the 24V low-voltage signal used by your thermostat, control board, and all safety circuits. When this component fails, the entire control circuit goes dark — the thermostat becomes unresponsive, the system won't heat or cool, and no error codes are generated because there's simply no power to produce them. If your air handler is completely unresponsive and your thermostat shows a blank screen despite a working power supply, this transformer is the first component to test.

• Specs: 40VA rated | Primary voltage: 120V AC | Secondary voltage: 24V AC | OEM part number HT01CN241 | Factory-matched electrical tolerance for reliable low-voltage output
• OEM vs Generic: This OEM unit is wound and tested to Carrier's exact VA rating and insulation standards. Undersized or off-tolerance generic transformers can overdraw current, trip the secondary fuse repeatedly, or fail prematurely under normal control circuit loads.
• Install difficulty: 2/5 — Disconnect all power before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or quick-connect terminals. Label all 24V wiring before disconnecting. Confirm incoming 120V is off before touching primary leads.
• Warranty: 1-year OEM factory warranty against defects in materials and workmanship. Orders ship same business day from our stocked warehouse.

Compatibility: Designed specifically for the Carrier FX4CNF018T00AAAA fan coil air handler. Always verify voltage ratings and VA requirements on your unit's data plate before ordering. Our HVAC parts specialists are available to confirm fitment — reach out before you order if you have any questions. In stock and ready to ship today.