OEM Carrier Transformer 40VA 120V to 24V for Model FA4CNF042015AAAA

This OEM Carrier transformer (part number HT01CN241) is the factory-specified replacement for the FA4CNF042015AAAA fan coil air handler. The transformer steps down 120V line voltage to 24V AC to power the low-voltage control circuit — including the thermostat, contactor coil, and control board. When this component fails, nothing in the system responds: the thermostat goes blank, the blower won't start, and the entire unit appears completely dead. It is one of the first components to check when diagnosing a total system shutdown with no obvious cause.

• Specs: 40VA rated | 120V primary input | 24V secondary output | Factory-matched windings and core spec for Carrier FA4CNF042015AAAA air handler applications
• OEM vs Generic: The OEM HT01CN241 transformer is wound to exact Carrier factory specifications, ensuring proper VA capacity to handle all connected 24V loads simultaneously. Undersized or off-spec generic transformers can overheat, trip thermal cutoffs, and damage connected control boards — making OEM the only reliable choice.
• Install difficulty: 2/5 — Shut off all power to the air handler before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, wire stripper, and a multimeter to confirm 24V output after installation. Label all low-voltage wiring before disconnecting.
• Warranty: 1-year OEM factory warranty against defects. Orders placed by 3 PM ET ship same business day from our climate-controlled warehouse.

Compatibility: Designed specifically for the Carrier FA4CNF042015AAAA fan coil air handler. Always verify the existing transformer's VA rating and primary/secondary voltages on the unit data plate before ordering to confirm fitment. Not sure if this is the right part? Our HVAC parts specialists verify compatibility before you buy — contact us before placing your order.