OEM Carrier Transformer 40VA 120V/24V for Model FB4CNF030L08ADAA

This OEM replacement transformer (part number HT01CN241) is the factory-specified control circuit transformer for the Carrier FB4CNF030L08ADAA fan coil air handler. The transformer steps down line voltage from 120V to the 24V signal required to power the thermostat, control board, and low-voltage control circuit. When this component fails, the entire control system loses power — the result is a completely unresponsive thermostat, no heating or cooling calls, and a system that appears completely dead despite the power being on.

• Specs: Primary voltage: 120V AC | Secondary voltage: 24V AC | VA rating: 40VA | OEM part number: HT01CN241 | Factory-matched output tolerance for stable low-voltage circuit operation
• OEM vs Generic: The OEM HT01CN241 transformer is wound to Carrier's exact VA and voltage specifications, ensuring the control board and thermostat receive stable, clean 24V power. Generic transformers with undersized VA ratings can brown out under load, causing erratic lockouts and premature control board failure.
• Install difficulty: 2/5 — Shut off all power to the air handler before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Label or photograph all low-voltage wiring connections at the secondary terminals before disconnecting. Verify 24V output with a multimeter after installation before restoring full power.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier FB4CNF030L08ADAA fan coil air handler. Always verify your existing transformer's primary/secondary voltages and VA rating against your unit's wiring diagram before ordering. If your system uses a higher VA demand due to accessory loads (humidifiers, UV lights), confirm total VA draw does not exceed 40VA. Our fitment team is available to verify compatibility before you order — same-day shipping on all in-stock OEM parts.