OEM Carrier Transformer 40VA 120V/24V for Model FB4CNF036L00ACAA

This OEM Carrier transformer (part number HT01CN241) is the factory-specified replacement for the FB4CNF036L00ACAA fan coil air handler. The transformer steps line voltage (120V) down to the 24V signal voltage required to power the entire control circuit — including the thermostat, contactor coil, and control board. When the transformer fails, nothing in the system responds: the thermostat goes blank, the air handler won't energize, and the outdoor unit remains off. A failed transformer is often caused by a short in the low-voltage wiring, so always inspect the 24V circuit before installing a replacement.

• Specs: 40VA rating | Primary: 120V | Secondary: 24V | Class 2 control circuit transformer | OEM part number HT01CN241
• OEM vs Generic: This OEM unit is wound to Carrier's exact VA rating and insulation class, ensuring clean 24V output under all load conditions. Generic transformers may be underrated, causing premature burnout if the low-voltage circuit draws peak current.
• Install difficulty: 2/5 — Shut off all power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter to verify 24V output after install. Photograph all wiring connections before disconnecting the old unit.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier FB4CNF036L00ACAA fan coil air handler. Verify your existing transformer's primary voltage, secondary voltage, and VA rating against your unit's data plate before ordering. If you are unsure of fitment, our HVAC parts team is available to verify compatibility before you purchase — same-day shipping on all in-stock orders.